yourProsoft

MFC "encountered an improper argument" message

2012-01-20T13:00:00.000-08:00

Hi there,

The story:

My MFC application "Schedule" that I work in 2 years ago faced by a very strange bug, the application is built using VC++, VS2008 on vista platform and configured to target vista platform by assigning WINVER=0x0600, _WIN32_WINNT=0x0600, _WIN32_WINDOWS=0x0410.

It runs perfectly on whatever machine running WinXP/Vista, other O.S.s are not available to test on. An overseas customer claimed a bug when she tried to save documents, her machine was HP-dv6000 with WinXP installed. I tolled her to upgrade the machine up to WinXP-SP3, but she upgraded up to Windows7 and the bug still exist.

The Bug is such a message says "encountered an improper argument", it emerged when she tried to save/open a file.

I googled every where but nobody has solution or a resolution, even in 2009 Microsoft tolled somebody that this issue is solved in VS2010, others talk about resource conflictions according to windows upgrades.

After long time I decided to investigate, where I spent 12 hours of digging into MFC source code and files, and then discovered the problem.

It was the following statement that throws exception because of an invalided resource ID.

ENSURE(title.LoadString(nIDSTitle = bReplace ? AFX_IDS_SAVEFILE : AFX_IDS_SAVEFILECOPY));

"title" is a CString object that has to displayed in title bar of CFileDialog, it then be loaded first from a string resource AFX_IDS_SAVEFILE or AFX_IDS_SAVEFILECOPY which are not exist at the machine of the customer.

I successfully simulated the same bug on my own machine using the following lines of code.

CString temp;

ENSURE(temp.LoadString(0xF012));// 0xF012 is invalide

What is ENSURE()?

#define ENSURE(cond) ENSURE_THROW(cond, ::AfxThrowInvalidArgException() )

The following paragraph describes what is the macro ENSURE, I cut this paragraph from MSN and past it here.

The purpose of these macros is to improve the validation of parameters. The macros prevent further processing of incorrect parameters in your code. Unlike the ASSERT macros, the ENSURE macros throw an exception in addition to generating an assertion.

The macros behave in two ways, according to the project configuration. The macros call ASSERT and then throw an exception if the assertion fails. Thus, in Debug configurations (that is, where _DEBUG is defined) the macros produce an assertion and exception while in Release configurations, the macros produce only the exception (ASSERT does not evaluate the expression in Release configurations).

The macro ENSURE_ARG acts like the ENSURE macro.

To solve this bug I made two steps, First: I replaced CWinAPP::OnFileOpen using the following code:

//---------------------------------------------------------------------

void CScheduleApp::OnMyFileOpen()

{

//manual open using CFileDialog

CString strDocFileName = _T("");

CFileDialog *pDlg;

pDlg = new CFileDialog (TRUE,_T("yps"),strDocFileName,OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,

_T("File (*.yps)|*.yps|All Files (*.*)|*.*||"),NULL);

m_strCurFolder = m_strCurFolder.IsEmpty() ? GetParentFolder():m_strCurFolder;

pDlg->m_ofn.lpstrInitialDir = m_strCurFolder.GetBuffer(MAX_PATH);

pDlg->m_ofn.lpstrTitle = _T("فتح");

if(pDlg->DoModal()==IDOK)

{

strDocFileName = pDlg->GetPathName();

//the next line is optained from the following mfc source file

//C:\Program Files\Microsoft Visual Studio 9.0\VC\atlmfc\src\mfc\docmgr.cpp

AfxGetApp()->OpenDocumentFile(strDocFileName);

}

m_strCurFolder.ReleaseBuffer();

delete pDlg;

//Keep track of obtained folder as default for next open operation

m_strCurFolder = strDocFileName.IsEmpty() ? m_strCurFolder:

(strDocFileName.IsEmpty() ? _T(""):strDocFileName.Left(strDocFileName.ReverseFind('\\')+1));

//AfxMessageBox(m_strCurFolder);

theApp.WriteString(_T("CurUserFolder"),m_strCurFolder);

}

//---------------------------------------------------------------------

Second: I override CDocumment::DoSave() funtion to prevent it from calling AfxGetApp()->DoPromptFileName that uses the buggy resource, here is the code:

//---------------------------------------------------------------------

BOOL CScheduleDoc::DoSave(LPCTSTR lpszPathName, BOOL bReplace)

{

CString newName = lpszPathName;

if (newName.IsEmpty())

{

CDocTemplate* pTemplate = GetDocTemplate();

ASSERT(pTemplate != NULL);

newName = m_strPathName;

if (bReplace && newName.IsEmpty())

{

newName = m_strTitle;

// check for dubious filename

int iBad = newName.FindOneOf(_T(":/\\"));

if (iBad != -1)

newName.ReleaseBuffer(iBad);

// append the default suffix if there is one

CString strExt;

if (pTemplate->GetDocString(strExt, CDocTemplate::filterExt) &&

!strExt.IsEmpty())

{

ASSERT(strExt[0] == '.');

int iStart = 0;

newName += strExt.Tokenize(_T(";"), iStart);

}

//Replace the bug lines with a new technique

//if (!AfxGetApp()->DoPromptFileName(newName,

// bReplace ? AFX_IDS_SAVEFILE : AFX_IDS_SAVEFILECOPY,

// OFN_HIDEREADONLY | OFN_PATHMUSTEXIST, FALSE, pTemplate))

// return FALSE; // don't even attempt to save

if(!MyDoPromptFileName(newName,bReplace))

return false;

}

CWaitCursor wait;

if (!OnSaveDocument(newName))

{

if (lpszPathName == NULL)

{

// be sure to delete the file

TRY

{

CFile::Remove(newName);

}

CATCH_ALL(e)

{

//the normal place for the following Macro is in mfc\stdafx.h

//I bring it here becuase it is used only here and I have no plan to use it anywhere

#define DELETE_EXCEPTION(e) do { if(e) { e->Delete(); } } while (0)

TRACE(traceAppMsg, 0, "Warning: failed to delete file after failed SaveAs.\n");

DELETE_EXCEPTION(e);

}

END_CATCH_ALL

}

return FALSE;

}

// reset the title and change the document name

if (bReplace)

SetPathName(newName);

return TRUE; // success

}

BOOL CScheduleDoc::MyDoPromptFileName(CString& fileName, bool bReplace)

{

CFileDialog *pDlg;

pDlg = new CFileDialog (FALSE,_T("yps"),fileName,OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,

_T("Timetable File (*.yps)|*.yps|All Files (*.*)|*.*||"),NULL);

CString title = bReplace ? _T("حفظ جدول الحصص"):_T("حفظ جدول الحصص في ملف آخر");

pDlg->m_ofn.lpstrTitle = title;

if(pDlg->DoModal()!=IDOK)

return FALSE;

fileName=pDlg->GetPathName();

return TRUE;

}

//---------------------------------------------------------------------

C# access webservice from behind proxy

2011-06-30T06:52:00.000-07:00

I was trying to use C# .NET desktop application to access a webservice from my office, the web-service is behind a proxy firewall, I was annoyed by seeing the following error message

"- The request failed with HTTP status 407: Proxy Authentication Required"

By googling I found a solution that enables me to disable proxy "http://stackoverflow.com/questions/2131933/http-407-proxy-authentication-error-when-calling-a-web-service"

To disable the proxy, in the App.config file add the following configuration

<system.net>
<defaultProxy enabled="false" useDefaultCredentials="false">
<proxy/>
<bypasslist/>
<module/>
</defaultProxy>
</system.net>

To enable the proxy and to use the default proxy settings(specified in IE) add this configuration in your App.config

<system.net>
<defaultProxy enabled="true" useDefaultCredentials="true">
<proxy/>
<bypasslist/>
<module/>
</defaultProxy>
</system.net>

Godaddy Email problem with hosted applications

2011-05-30T10:32:00.000-07:00

My web application hosted on Godaddy can't send email messages after being uploaded there. But it works normally and can send email messages from my local machine. I tried many variations for SMTP configuration as follows but no-way for success:

1- This configuration is working from my local machine

· SMTP: smtp.mydomain.com

· Port: 25

· SSL: not enabled

· user: webmaster@mydomain.com

· password: **********

2- This configuration is not working

· SMTP: smtpout.secureserver.net

· Port: 25 or 80 or 3535 or 587

· SSL: not enabled

· Cedential user: webmaster@mydomain.com

· Cedential password: **********

3- This configuration is not working

· SMTP: smtp.secureserver.net

· Port: 25 or 80 or 3535 or 587

· SSL: not enabled

· Cedential user: webmaster@mydomain.com

· Cedential password: **********

I found the solution, and it was so old problem, since 2005, I found it in the following link:

http://forums.asp.net/t/939893.aspx/1?Problem+with+System+Net+Mail+on+GoDaddy

The problem is that SMTP-server is not smtpout.secureserver.net as Godaddy tells me. But It is relay-hosting.secureserver.net that nobody tells me at all. There is no need for user name or password, relay is open for 1000 message per day for hosted applications.

jQuery simplemodal plugin typeError: 'tagName' is null or not an object.

2011-05-30T10:06:00.000-07:00

Many thanks for Eric's effort he made to create the great simple modal jQuery plugin.

http://www.ericmmartin.com/projects/simplemodal-demos/

I found a bug then fixed it, the bug is in $.modal.impl.create function , I think it is not new for you, where you mentioned the solution when you commented to use 'form' instead 'body' for the property appendTo.

First: the comment have to be modified to become {use '#aspnetForm'} instead of {use 'form'}
Second: in line number 344, there is still hard coding problem of the word 'body', as follows.

// add styling and attributes to the data
// append to body to get correct dimensions, then move to wrap
s.d.data = data
.attr('id', data.attr('id') || s.o.dataId)
.addClass('simplemodal-data')
.css($.extend(s.o.dataCss, {
display: 'none'
}))
.appendTo('body');

I replaced the hard coded word with s.o.appendTo object such like {.appendTo(s.o.appendTo);}, and everything goes right.

Firefox problem with iframe

2011-03-28T01:01:00.000-07:00

|
|..primery.aspx
|..rootpage.aspx
|..|-l1
     |-l2
       |-l3
         |..test.htm
|

I have HTML page (i.e. test.htm) in a website say (http://172.16.16.20), the page is deeply located into a 3rd level folder, to access the page you have to write the URL as follows (http:/172.16.16.20/l1/l2/l3/test.htm), test.htm has iframe element with src="/rootpage.aspx" like following:

<ifram src="/rootpage.aspx"></iframe>
..

The "rootpage.aspx" with another page named "primary.aspx" are located in the root folder of the website. And primary.aspx looks like the following:

...

...

If you open primery.aspx , it is normal to expect to see iframe of tset.htm that contain iframe of rootpage.aspx. That is true for all browsers except Firefox. Unfortunately, Firefox will give the following error:

The page cannot be displayed

You have attempted to execute a CGI, ISAPI, or other executable program from a directory that does not allow programs to be executed.
Please try the following:
* Contact the Web site administrator if you believe this directory should allow execute access.
HTTP Error 403.1 - Forbidden: Execute access is denied.
Internet Information Services (IIS)
Technical Information (for support personnel)

I go to IIS>>website>>Properties>>HomeDirectory>>ApplicationSettings>>ExecutePermissions and make it Scripts and Executables. After that Firefox gave me the next error:

Server Error in '/' Application.

The resource cannot be found.
Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable. Please review the following URL and make sure that it is spelled correctly.
Requested URL: /l1/l2/l3/rootpage.aspx
Version Information: Microsoft .NET Framework Version:2.0.50727.3053; ASP.NET Version:2.0.50727.3053

From the last error message I understand that Firefox iframe.src property behaves differently than other browsers, I put "/" in front of the page name to tell the browser to go to root folder, but Firefox believes that root is relative to iframe context not browser context.

To solve the problem I modifed src="/rootpage.aspx" to become src="../../../rootpage.aspx"

Now everything goes right.

old "dbo" database owner prevents service broker from working properly - SQL 2005

2010-12-26T02:10:00.000-08:00

I have cloned a virtual copy of Win2003 server that has SQL2005 already installed. The new server is planned to be disconnected from the domain of the original server and run separately.

In SQL2005 I dropped all databases and restored my database that has service broker already enabled, the restored database was running very well on another server inside my old domain "AWQAF", this database also has a notification service running on top of a message queue called "messageQueue".

Service broker then didn't working as supposed or as it should to work like.

I tried to check the status of the service broker using the following statement:

SELECT is_broker_enabled FROM sys.databases WHERE name = 'AfaqCMS';

It gives me 0 result, a mean of service broker is disabled.

So, I tried to enable service broker using the following statement:

ALTER DATABASE [AfaqCMS] SET NEW_BROKER WITH ROLLBACK IMMEDIATE;

By trying to SEND/RECIVE messages using the following statements, I got dialog created without messages transmission:

DECLARE @NotificationDialog uniqueidentifier;

SET QUOTED_IDENTIFIER ON;

BEGIN DIALOG CONVERSATION @NotificationDialog

FROM SERVICE ChangeNotifications

TO SERVICE 'ChangeNotifications'

ON CONTRACT [http://schemas.microsoft.com/SQL/Notifications/PostQueryNotification]

WITH ENCRYPTION = OFF;

SEND

ON CONVERSATION @NotificationDialog

MESSAGE TYPE [http://schemas.microsoft.com/SQL/Notifications/QueryNotification] (N'CommentHits');

SELECT @NotificationDialog;

RECEIVE * FROM ChangeMessagesQueue ;

By checking transmission queue of the system I found some errors around the original owner of the restored database.

SELECT * FROM sys.transmission_queue

A filed called "transmission_status" is containing the following exception:

An exception occurred while enqueueing a message in the target queue.

Error: 15404, State: 11.

Could not obtain information about Windows NT group/user 'AWQAF\adm_walghool', error code 0x534.

By deleting 'AWQAF\adm_walghool' from all locations it can be existed in, I got another status:

An exception occurred while enqueueing a message in the target queue.

Error: 15517, State: 1.

Cannot execute as the database principal because the principal "dbo" does not exist,

this type of principal cannot be impersonated, or you do not have permission.

Now I realized that it is the database owner that prevents service broker from working properly, So I run the following statement to get every things working successfully again:

ALTER AUTHORIZATION ON DATABASE::[AfaqCMS] TO [SA]

Anthother statement can be used also:

USE AfaqCMS

EXEC dbo.sp_changedbowner @loginame = N'zakauser', @map = false

What is the difference between ISO 9660, Joliet and UDF?

2010-08-02T23:29:00.000-07:00

CD-ROM File Systems

An ISO 9660 file system is a standard CD-ROM file system. Full ISO format requires all upper case characters or numbers, no spaces, very limited special characters, and no more than 30 characters in the name.

Joliet is the name of an extension to the ISO 9660 file system. Joliet format permits 64-character file names with lower-case alpha and other relaxed restrictions. It also relaxes the ISO requirement for directory nesting to no more than eight levels. It doesn't hurt to include the Joliet Directory if the names conform.

UDF is a hybrid filesystem that uses both UDF and ISO 9660. Also called a UDF bridge, it was commonly used until Microsoft incorporated support for UDF in its operating system. UDF permits 127 16-bit Unicode characters, or 254 8-bit Unicode characters. If any character in any name is not in the list of legal 8-bit Unicode characters, all names will be represented in 16-bit Unicode.

However Joliet is no longer needed since the ISO 9660 standard has been extended in 3 different levels:
Level 1: Filename cannot be longer than 8 chars , Filename extention cannot be longer than 3 chars.
Level 2: Filename can be up to 255 chars long.
Level 3: Same as level 2 but files can be written in multiple extents (-> Packet writing).

Normally a Mac can read both ISO 9660 and Joliet CDs.

ClickOnce does not install fonts - Install fonts using C#

2010-06-28T21:55:00.000-07:00

ClickOnce does not install fonts. ClickOnce is designed to be a non-impactful install, and installing fonts is considered impactful to a user's computer. ClickOnce is only a deployment technology, it does not offer any support for font installation, so this operation requires extra coding. We have to code the font installation logic in the application. To install font on client machines, we have to create code just like the following.

ClickOnce deloyment normally does not touch the system directories. This is an important difference with MSI deployment technology. ClickOnce deployment does not cover:
· "Install to GAC"(GAC is another system directory)
· "Write to Registry"
· "Install for All Users" etc... While these can all be done with MSI:

Take a look to "Key Differences" between ClickOnce and MSI:
http://msdn.microsoft.com/en-us/library/142dbbz4(VS.90).aspx

So we have to code ourselves for the font installation, first: write file from embedded resource, second: add font to windows resources, third: add registry entry so the font is also available next session, finally: solve GDI+ bug, where GDI+ must be notified with this new added font, so, a scalable font resource file needs to be created, this scalable font resource file stores the name of a TrueType font file so that GDI knows where to find the file. To create a scalable font resource file, call the GDI function CreateScalableFontResource with an integer flag, the name of the font resource file to be generated, an existing TrueType font file name, and the path to the files if they do not contain a complete path.

First: Special thanks for following threads:

http://www.devnewsgroups.net/group/microsoft.public.dotnet.framework/topic52983.aspx
http://www.daniweb.com/forums/thread231795.html
http://www.dotnetmonster.com/Uwe/Forum.aspx/winform/18215/ClickOnce-deployment-include-font

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Win32;
using System.Runtime.InteropServices;
using System.Drawing.Text;
using System.Windows.Forms;
namespace myNameSpace

{
class InstallFonts
{
// PInvoke to look up fonts path
[DllImport("shfolder.dll", CharSet = CharSet.Auto)]
private static extern int SHGetFolderPath(IntPtr hwndOwner, int nFolder, IntPtr hToken, int dwFlags, StringBuilder lpszPath);

private const int CSIDL_FONTS = 0x0014;
private const int MAX_PATH = 260;
private static string GetFontsPath()
{
StringBuilder sb = new StringBuilder(MAX_PATH);
SHGetFolderPath(IntPtr.Zero, CSIDL_FONTS, IntPtr.Zero, 0, sb);
return sb.ToString();
}

// PInvoke to 'register' fonts and broadcast addition

[DllImport("gdi32.dll")]
private static extern int AddFontResource(string lpszFilename);

[DllImport("gdi32", EntryPoint = "RemoveFontResource")]
private static extern bool RemoveFontResourceW(string lpFileName);

[DllImport("gdi32.dll")]
private static extern int CreateScalableFontResource(uint fdwHidden, string lpszFontRes, string lpszFontFile, string lpszCurrentPath);

private static IntPtr HWND_BROADCAST = new IntPtr(0xffff);
private const uint WM_FONTCHANGE = 0x001D;

[DllImport("user32.dll", CharSet = CharSet.Auto)]
private static extern int SendMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);

public static void InstallFont()
{

string fontsPath = GetFontsPath();
string ttfFile9 = System.IO.Path.Combine(fontsPath, "V100009_.TTF"); ;
string fotFile9 = System.IO.Path.Combine(fontsPath, "V100009_.FOT"); ;

int ret;
if (!System.IO.File.Exists(ttfFile9))
{
//Write file from embedded resource
System.IO.File.WriteAllBytes(ttfFile9, MyFonts.V100009_);
//Allow GDI+ to be notified and determines the new fonts
//to install a TrueType font, a scalable font resource file needs to be
//created. This scalable font resource file stores the name of a TrueType
//font file so that GDI knows where to find the file. To create a scalable
//font resource file, call the GDI function CreateScalableFontResource with
//an integer flag, the name of the font resource file to be generated, an
//existing TrueType font file name, and the path to the files if they do not
//contain a complete path.
ret = CreateScalableFontResource(0, fotFile9, ttfFile9, String.Empty);
//Add font resource
ret = AddFontResource(fotFile9);
//Add registry entry so the font is also available next session
Registry.SetValue(@"HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Fonts", "C39HrP36DlTt (TrueType)", "V100009_.TTF", RegistryValueKind.String);

//Broadcast to let all top-level windows know about change
ret = SendMessage(HWND_BROADCAST, WM_FONTCHANGE, new IntPtr(0), new IntPtr(0));
//Work around to use font after installing without restarting the installing application
//It is GDI+ bug not .NET bug,
PrivateFontCollection oPFC9 = new PrivateFontCollection();
oPFC9.AddFontFile(ttfFile9);
}
}
}
}

An error occurred creating the configuration section handler for system.serviceModel/bindings

2010-06-22T06:57:00.000-07:00

Suddenly I got a problem when trying to access a web service,
the problem only occurred on my PC that has "Vista SP1 x64"
operating system, my workmates hasn't this problem at all, this is the exception
string appeared:

System.TypeInitializationException: The type initializer for
'my internal class name' threw an exception. --->
System.Configuration.ConfigurationErrorsException: An error occurred creating
the configuration section handler for system.serviceModel/bindings: Could not
load type
'System.Security.Authentication.ExtendedProtection.Configuration.ExtendedProtectionPolicyElement'
from assembly 'System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.
(D:\Projects\Hajj1431\Sources\Desktop\Hajj\bin\Release\Hajj.exe.Config line 38)
---> System.TypeLoadException: Could not load type
'System.Security.Authentication.ExtendedProtection.Configuration.ExtendedProtectionPolicyElement'
from assembly 'System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.

I googled and found some thing similar

here,

here,

here and

here. All of them points to a corrupted windows update with code KB982168, I
spend long time searching about KB982168 or any thing similar but nothing. Where
all of the previous threads were talking about Win2003 and WinXP updates.

I tried to restore my operating system to old date but Windows
Restore was disabled by group policy created by Domain Admin.

I tried to go deep in the problem to find which assembly cause
the problem but it seems it is some thing larger than a single assembly.

After long time of try and error I reached a solution by
installing Vista Service Pack 2.

Where, I noticed that Microsoft announced it will not support
Vista without SP2, so, I realized that any update my not work properly without
SP2, again searching, I found x64 version of mentioned SP2, it takes an hour to
download and another hour or more to install, but finally web-services is back
to work again.

Thanks god ...

Service Pack 2 (KB948465):

It is 745MB size and can be downloaded from this link:

http://www.microsoft.com/downloads/details.aspx?FamilyID=8ad69826-03d4-488c-8f26-074800c55bc3&displaylang=en&displaylang=en

The remote server returned an error: (502) Bad Gateway.

2010-05-18T22:22:00.000-07:00

The remote server returned an error: (502) Bad Gateway.

Simply I want to access internet-world from inside my web-application using the following code.

public static string BrowseURL(string url)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.KeepAlive = false;
request.ProtocolVersion = HttpVersion.Version10;
request.Method = "GET";
request.Credentials = CredentialCache.DefaultCredentials;
//
request.Proxy = WebProxy.GetDefaultProxy();
request.Proxy.Credentials = CredentialCache.DefaultCredentials;
//
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.GetEncoding(response.CharacterSet));
string responseData = reader.ReadToEnd();
return responseData;
}

On my development machine it works fine, but on production server I faced a problem of "Bad Gateway" when reaching GetResponse(), I realized that it was an authentication problem, and after some google_ing, I found a good thread that speaks about solving Proxy problems with authentication. Now, the following code is working properly on my production environment.

public static string BrowseURL(string url)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.KeepAlive = false;
request.ProtocolVersion = HttpVersion.Version10;
request.Method = "GET";
request.Credentials = CredentialCache.DefaultCredentials;
//that is the solution
WebProxy proxy = new WebProxy("proxy ");
proxy.Credentials = new NetworkCredential("userName", "Password", "Domain");
request.Proxy = proxy;
//
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.GetEncoding(response.CharacterSet));
string responseData = reader.ReadToEnd();
return responseData;
}

Conditional buidl Events using Viusal Studio 2008

2010-05-15T01:11:00.000-07:00

Sometimes you need some extra actions to be trigged after build, eg. copy exe files. To add an extra action, go to project properties and select “Build Events” tab. You can add the additional actions before and after build process.

But what if some conditions are needed to check before performing your action. !

Two things you have to investe in order to know how to make conditional build event in VS2008, first, is the command macros introduced by Microsoft in VS2008, second, is the batch file ".BAT" commands.

Command Macros are here.
BAT Commands are here.

Example:

IF NOT $(ConfigurationName) == Release GOTO end
Copy "$(SolutionDir)\$(ConfigurationName).exe" "$(TargetPath)"
:end

C++ Macro Concatination

2010-05-05T07:39:00.000-07:00

You can use ## operator (double number sign) to concatinate two tokens (text or arguments) in macro invocation.

Example:

enum Types {T1,T2};
#define MakeDrivedClass(name, type) class name##type : public type##Base{}
MakeDrivedClass(CMy,t1);

Output:
class CMyT1 : public T1Base {};

500.19 IIS7 ERROR

2010-04-03T04:47:00.000-07:00

After createing a new ASP.NET application, and after publishing to certain folder, IIS7 refused to open the published site because of 500.19 error, IIS7 said that the requested page cannot be accessed because the related configuration data for the page is invalid.

But, in fact it is a security issues that prevent mister IIS7 from accessing web.config file. Particularly, it was computername\IIS_IUSRS that must take some permisions, read this article for more information.

Solution:
Simply add the following groups into security tab to solve this problem:
1- Authenticated Users
2- Users (computername\Users)

Allow only one instance of any Windows Form, C#

2010-03-16T21:45:00.000-07:00

The ability to load forms once, is something essential in many applications. But, this is a simple way to do that:

public Boolean IsFormAlreadyLoaded(string formToLoadName)
{    //Allow only one instance of any MDI child form in your MDI application
    foreach (Form frmChild in this.MdiChildren)
    {        if (frmChild.Name == formToLoadName)
        {
            frmChild.Activate();
            return true;
        }
    }
    return false;
}

Printer capabilities

2010-03-15T21:34:00.000-07:00

This is an excelent article about printing essentials, and, here is my own experiments using some different printers:

HP Officejet Pro All-in-One

HP Color LaserJet 3800

KONICA MINOLTA mc7450 PS

ClickOnce signing error and its solution :)

2010-03-09T02:04:00.000-08:00

This is the error:
error: 0x80880253
The signer's certificate is not valid for signing.
SignTool Error: An error occurred while attempting to sign: bin\Debug\app.publish\\setup.exe

A very good work but not work with me: http://www.may.be/renewcert/

A very good comment that brings me to the road and solve the problem:
http://social.msdn.microsoft.com/Forums/en/winformssetup/thread/cebc2dff-1418-4be4-b3f7-9e158ed6b573

This the magic comment:
Are you signing your ClickOnce deployment? If you go to the Signing tab for your project, do you have a certificate selected?

If you are just pushing updates for the same application, you will want to track down the certificate file (pfx) you used to use and sign with it instead of creating a new one, so the deployment does not think you created a new certificate.
If you are just deploying something new, you can create a test certificate and use that.
RobinS.
GoldMail.com

Identify yourself with Certificates

2010-03-07T22:55:00.000-08:00

What is PFX file?
This file type is an acronym of "Personal Information Exchange" that can be opened with "Microsoft Certificate Manager or Certificate Import Wizard".

This file is an Encrypted security file that stores SSL secure certificates used to authenticate a person or device, such as a computer or Web server; requires a password to be opened; can be installed by right-clicking the file and selecting "Install PFX."

More than one certificate can be stored in a single file in the following formats:

PFX,P12: Personal Information Exchange
P7B: Cryptographic Message Syntax Standard-PKCS#7 Certificate
SST: Microsoft Serialized Certificate Store

What SSL Is and Why You Need It?

Doing business online without SSL is like leaving customer credit card numbers on the counter or offering a dressing room without a door

An SSL certificate is a bit of code on your web server that provides security for online communications. When a web browser contacts your secured web site, the SSL certificate enables an encrypted connection. It’s kind of like sealing a letter in an envelope before sending it through the mail.

SSL certificates also inspire trust because each SSL certificate contains identification information. When you request an SSL certificate, a third party (such as Thawte or VeriSign) verifies your organization’s information and issues a unique certificate to you with that information. This is known as the authentication process.

An SSL certificate, or secure certificate, is a file installed on a secure Web server that identifies a website. This digital certificate establishes the identity and authenticity of the company or merchant so that online shoppers can trust that the website is secure and reliable. In order to verify that these sites are legitimate (they are who they say they are), the companies and their websites are verified by a third party, such as Verisign or Thawte.

Once the verification company establishes the legitimacy of an organization and the associated website, they will issue an SSL certificate (for the small fee of a few hundred dollars). This digital certificate is installed on the Web server and will be viewable when a user enters a secure area of the website. You can tell you are visiting a secure page when the URL starts with "https." To view the certificate, click the lock icon near one of the edges of your browser window.

Because digital certificates verify a company's current status, they do not last forever. SSL certificates typically expire every one to three years. If the certificate is not renewed in time, you may see an alert box pop up that says "This website's certificate has expired." This error has nothing to do with you or your computer, but is displayed because the Web server you connected to has not renewed its SSL certificate. While this does not necessarily mean the site is fraudulent, it does show that the site is less than professional.

What Happens between the Web Browser and Server?

1.A browser attempts to connect to a web site secured with SSL. The browser requests that the web server identify itself.
2.The server sends the browser a copy of its SSL certificate.
3.The browser checks whether it trusts the SSL certificate. If so, it sends a message to the server.
4.The server sends back a digitally signed acknowledgement to start an SSL encrypted session.
5.Encrypted data is shared between the browser and the server.

Continue reading ...
http://www.thawte.com/resources/ssl-information-center/get-started-with-ssl/index.html
http://www.thawte.com/resources/ssl-information-center/get-started-with-ssl/how-ssl-works/index.html

List of comercial certificate authorities
http://msdn.microsoft.com/en-us/library/ms995347.aspx

AOL (http://www.aol.com)
A-Trust (http://www.a-trust.at)
Arge Daten (http://www.signatur.rtr.at/de/providers/providers/argedaten.html)
AS Sertifitseerimiskeskuse (http://www.sk.ee)
Asociacion Nacional del Notariado Mexicano (http://www.notariadomexicano.org.mx)
Austria Telekom-Control Commission (http://www.signatur.rtr.at)
Autoridade Certificadora Raiz Brasileira (http://www.icpbrasil.gov.br)
Autoridad de Certificacion Firmaprofesional
Baltimore (http://www.baltimore.com)
Belgacom E-Trust (http://www.e-trust.be)
CC Signet (http://www.signet.pl)
CAMERFIRMA (http://www.camerfirma.com)
Certic?mara S.A. (http://www.certicamara.com/)
Certisign (http://www.certisign.com.br/)
CertPlus (http://www.certplus.com)
Colegio de Registradores
Comodo Group (http://www.comodogroup.com/)
ComSign (http://www.ComSign.co.il)
Correo
Deutsche Telekom (http://www.telekom.de)
DST (http://www.digsigtrust.com/)
Entrust (http://www.entrust.com/certificate_services/index.htm)
eSign (http://www.esign.com.au/)
EUnet International (http://www.eunet.fi/)
FESTE (http://www.feste.org/)
First Data Digital Certificates (http://www.firstdata.com/index.jsp)
FNMT (http://www.ceres.fnmt.es/)
Gatekeeper Root CA (http://www.agimo.gov.au/infrastructure/gatekeeper)
GeoTrust (http://www.geotrust.com)
GlobalSign (http://www.globalsign.com/)
GoDaddy (http://www.godaddy.com)
Hongkong Post (http://www.hongkongpost.gov.hk/product/cps/ecert/index.html))
IPS SERVIDORES (http://www.ips.es/)
KMD (http://www.kmd-ca.dk)
NetLock (http://www.netlock.hu/)
Post.Trust (http://www.post.trust.ie/)
PTT Post (http://www.ptt-post.nl)
Quovadis (http://www.quovadis.bm/)
RSA (http://www.rsasecurity.com/)
Saunalahden Serveri (http://www.saunalahti.fi/)
SECOM Trust.net (http://www.secomtrust.net)
SecureNet (http://www.securenetasia.com/)
SecureSign (http://www2.jcsinc.co.jp)
Serasa (http://www.serasa.com/)
SIA (https://ca.sia.it/)
Sonera (http://www.sonera.com/)
Spanish Property & Commerce Registry (https://www.registradores.org))
TC TrustCenter (http://www.trustcenter.de/)
TDC (http://www.tdc.dk)
Thawte (http://www.thawte.com/)
Trustis Limited (http://www.trustis.com)
TW Government Root Certification Authority
Unizeto Certum (http://www.certum.pl)
UserTRUST (http://www.usertrust.com/)
ValiCert (http://www.valicert.com/)
Verisign (http://www.verisign.com/)
Visa
Wells Fargo Root Certificate Authority (http://www.wellsfargo.com/certpolicy)
XRamp (http://www.xramp.com)

Some Internet culture around Flash

2010-03-04T00:27:00.000-08:00

Adob, Learn Flash Professional CS4:
Learn how to use Flash Professional CS4 with tutorials selected by experts at Adobe.There's everything from Getting Started for beginners, to New Features, Workflows, and Overviews.

http://tv.adobe.com/show/learn-flash-professional-cs4/

PixlToLife: learning made simple
Contians free flash tutorials: http://www.pixel2life.com/tutorials/adobe_flash/
Also, includes these good tutorials:
1- Making a Photoshoot Effect With jQuery & CSS: http://www.pixel2life.com/viewtutorial/76739/making_a_photoshoot_effect_with_jquery_css/
Which depends on the following tutorial:
jQuery PhotoShoot Plugin 1.0: http://tutorialzine.com/2010/02/jquery-photoshoot-plugin/
Where the author uses images from Flicker.
Flicker: is huge store of shared images, http://www.flickr.com/

2- Creating Ripples in the Medici Fountain: http://www.pixel2life.com/viewtutorial/76115/creating_ripples_in_the_medici_fountain/

Simplified jQuery Poll-down menu, only an anchor and a div elements

2010-03-01T22:10:00.000-08:00

This code is adopted from another original article:

It is a simple poll down menu construct from <a> alement and <div> element, just like that:
1.<a id="anchor" onclick="return false;" href="">Menu title</a>
2.<div id="div" style="display:none;position:absolute; z-index:1000;">
3.    <a href="">element1 title</a>
4.    <a href="">element2 title</a>
5.</div>

function MakeADIVMenu(anchor,div) {    var timeoutID = -1;
    $('a#' + anchor)
    .hover(
        function() {
            clearTimeout(timeoutID);
            $('#' + div).css('position', 'absolute');
            $('#' + div).css('top', $('a#' + anchor).position().top);
            $('#' + div).css('left', $('a#' + anchor).position().left - ($('#' + div).width()/2));
            $('#' + div).css({zIndex:20}).show();
        },
        function() { timeoutID = setTimeout(function() { $('#' + div).hide(); }, 2000); }
    );

    $('#' + div)
    .hover(
        function() {
            clearTimeout(timeoutID);
            $(this)
            .each(function() {
            $(this).css('position', 'absolute');
            $(this).css('top', $('a#' + anchor).position().top);
            $(this).css('left', $('a#' + anchor).position().left - ($(this).width()/2));
            $(this).css({ zIndex: 20 }).show();});
        },
        function() { $(this).hide(); }
    );
    //1.<a id="anchor" onclick="return false;" href="">
    //2.<div id="div" style="display:none">
    //3. <a href="">element1</a>
    //4. <a href="">element2</a>
    //5.</div>
}

IE8 compatibility

2010-02-24T00:58:00.000-08:00

IE8 doesn't support many standard rules of W3C-CSS3. One of them is "background-origin" attribute, this attribute is used to define the origin of background-image, where it takes one value of (border, padding or content).

• IE up to version 7 defaults to background-origin: border;

• IE 8 default behavior is background-origin: padding;

But IE8 behaves like IE7 untill you tell him to behave like himself "IE8", that by adding the following meta tag to your HTML layout:

IE8, before adding meta tag

IE8, after adding meta tag to behave like IE8

The following selectors and attributes are not supported also in IE: and there are still more!!!

:root { sRules }

:nth-child() { sRules }

:nth-last-child() { sRules }

:nth-of-type() { sRules }

:nth-last-of-type() { sRules }

:last-child { sRules }
:first-of-type { sRules }

:last-of-type { sRules }

:only-child { sRules }

:only-of-type { sRules }

:empty { sRules }

:target { sRules }

:not(X) { sRules }

:enabled { sRules }

:disabled { sRules }

:checked { sRules }
:indeterminate { sRules }

:default { sRules }

:valid { sRules }
:invalid { sRules }

:in-range { sRules }

:out-of-range { sRules }
:required { sRules }
:optional { sRules }
:read-only { sRules }
:read-write { sRules }

::before { sRules }
::after { sRules }
::first-letter { sRules }

::first-line { sRules }

::selection { sRules }

::value { sRules }

::choices { sRules }

::repeat-item { sRules }

::repeat-index { sRules }

{ color-profile : sProfile }

{ rendering-intent : sIntent }

{ background : sBackground1,sBackground2, etc. }

{ background-clip : sClip }

{ background-origin : sOrigin }

{ background-break : sBreak }

{ background-size : sSize }

{ font-effect : sEffect }

{ font-emphasize : sEmphasize }

{ font-size-adjust : sSizeAdjust }

{ font-smooth : sSmooth }

{ font-stretch : sStretch }
{ hanging-punctuation : sHangingPunctuation }
{ punctuation-trim : sTrim }

{ border-break : sBreak }
{ border-image : sImage }
{ border-radius : sRadius }

{ box-shadow : sShadow }

DIVs-tree size-measure and offset-calculation recurcive-algorithm, O(n)

2010-02-12T23:11:00.000-08:00

<div> Tree size-measure and offset-calculation recurcive-algorithm, O(n) complexity

I have a tree of <div>s and want a rendering algorithm to calculate total size and detailed offests, so, each <div> will implement the following recursive algorithm.

<div style="block">

   <div style="block"><div style="inline"></div><div style="inline"></div><div style="inline"></div></div>
   <div style="block"><div style="inline"></div><div style="inline"></div><div style="inline"></div></div>
   <div style="block"><div style="inline"></div><div style="inline"></div><div style="inline"></div></div>
</div>

Measure Algorithm:
. I'm <div> object, that is the single input to the algorithm
. I have mySize of (X,Y) and myOffset of (x,y)
. Initilaize a runningOffset to equal myOffset
. Initialize runningInnerSize with (0,0)
. Loop through my children:
    . If child flow is INLINE, then, set child offset to runningOffset
    . If child flow is BLOCK, then, set child offset as follows:
        . childOffset.x = myOffset.x
        . childOffset.y = myOffset.y + runningInnserSize.height
    . Calculate childSize by recursive call to Measure Algorithm
        . childSize = Measure Algorithm
    . If child flow is INLINE:
        . Increment runningInnerSize.width by childSize.width
        . Keep runningInnerSize.height unchanged if it is longer than childSize.height
           . else  runningInnerSize.height=childSize.height
        . Prepare runningOffset for next sibling "next child"
           . runningOffset.x increment by childSize.width
    . If child flow is BLOCK:
        . Increment runningInnerSize.height by childSize.height

        . Keep runningInnerSize.width unchanged if it is longer than childSize.width
           . else runningInnerSize.width = childSize.width
        . Prepare runningOffset for next sibling "next child"
            . runningOffset.x increment by childSize.width
    . Change my size to srround runningInnerSize
    . Keep track of runningInnerSize for latter use
    . Return my size to the caller
. End of Algorithm

Lambada as Predicate method, c#3.5

2010-02-10T22:21:00.000-08:00

{
    List<string> ZoneList = new List();
.
.
.
    for (int i = 0; i > 10; i++)

    {
       ZoneList.Add(i.ToString());
    }

.
.
.
    if (ZoneList.Exists(listItem => listItem != notExistedWord))

    {
       ZoneList.Add(notExistedWord);
    }
}

ZoneList.Exists(Predicate<string> match) is a List method that needs predicate-method as input paramter, the Predicate-method must has a string input paramter and Boolean output parameter, the string input paramter will be used to carry one by one item of the List items for being proccessed inside predicate-method, alternativly, we can use lambada expression listItem => listItem==searchedWord, where left side of => is concidered input for the right side, this expression can be assigned to delegate just like that:

delegate Boolean SearchDelegate(string listItem);
SearchDelegate exists = listItem => listItem==searchedWord

searchedWord is a variable that must be explicitly defined before lambada is defined, searchedWord will be stored for use even if it goes out of scope, this is one rule of many lambada-variable-scope rules.

gdiplus.lib is inside Windows SDK

2010-01-29T06:32:00.000-08:00

I'm developing my C++ applications on VS2008 and Vista OS, and need to add gdiplus.lib on my Project/Properties/Linker/General/Application&Liberary&Directoris.

1- First read those links (if you prefer):
Microsoft Windows SDK Blog
Windows SDK
Which SDK is Right for Me?
Using GDI+ with MFC or native C/VC++

2- Download and install ISO image of:
Windows SDK for Windows Server 2008 and .NET Framework 3.5
It provides the documentation, samples, header files, libraries, and tools (including C++ compilers) that you need to develop applications to run on Windows Server 2008 and the .NET Framework 3.5. This SDK is compatible with Visual Studio® 2008, including Visual Studio Express Editions, which are available free of charge.

3- Download and installing exe file of:
Microsoft Visual Studio 2008 Service Pack 1 Update (KB974479)
There is a known incompatibility between the Microsoft Windows Software Development Kit for Windows Server 2008 and .NET Framework 3.5, and Microsoft Visual Studio 2008 Service Pack 1 which is manifested when the ATL Security Update (KB971092) is installed. This update addresses the issue. After you install this update, you may have to restart your computer.

Use Virtual-CD to open ISO

Allow autorun to start installing SDK

When installation is finished, then restart and then install KB974479

Right click project name and select Properties

Add libarary directory to General/Additional Library Directories

Add Gdiplus.lib to input/Aditional Dependencies, you may instead use "#pragma comment(lib,"gdiplus.lib")"

Adjust your stdafx.h by adding appropriate header, namespace and pragma "if pragma is needed"
declare tokken member in CWinAppEx drived class

Initialize GDI+ inside CwinAppEx::InitInstance

Finalize GDI+ at the end of your application CWinAppEx::ExitInstance
Start using GDI+ functionality to render your document

GDI+ overview

2010-01-27T22:18:00.000-08:00

GDI+

Download details: Platform SDK Redistributable: GDI+

Purpose. Microsoft Windows GDI+ is a class-based API for C/C++ programmers. It enables applications to use graphics and formatted text on both the video display and the printer.

Three parts of GDI+:

1- 2-D vector graphics
2- Imaging
3- Typography

The Structure of the Class-Based Interface:

The C++ interface to Microsoft Windows GDI+ contains about 40 classes, 50 enumerations, and 6 structures. There are also a few functions that are not members of any class. The Graphics class is the core of the GDI+ interface; it is the class that actually draws lines, curves, figures, images, and text.

Many classes work together with the Graphics class. For example, the Graphics::DrawLine method receives a pointer to a Pen object, which holds attributes (color, width, dash style, and the like) of the line to be drawn. The Graphics::FillRectangle method can receive a pointer to a LinearGradientBrush object, which works with the Graphics object to fill a rectangle with a gradually changing color. Font and StringFormat objects influence the way a Graphics object draws text. A Matrix object stores and manipulates the world transformation of a Graphics object, which is used to rotate, scale, and flip images.

Certain classes serve primarily as structured data types. Some of those classes (for example, Rect, Point, and Size) are for general purposes. Others are for specialized purposes and are considered helper classes. For example, the BitmapData class is a helper for the Bitmap class, and the PathData class is a helper for the GraphicsPath class. GDI+ also defines a few structures that are used for organizing data. For example, the ColorMap structure holds a pair of Color objects that form one entry in a color conversion table.

GDI+ defines several enumerations, which are collections of related constants. For example, the LineJoin enumeration contains the elements LineJoinBevel, LineJoinMiter, and LineJoinRound, which specify styles that can be used to join two lines.

GDI+ provides a few functions that are not part of any class. Two of those functions are GdiplusStartup and GdiplusShutdown. You must call GdiplusStartup before you make any other GDI+ calls, and you must call GdiplusShutdown when you have finished using GDI+.

New Features:

Gradient Brushes
GDI+ expands on Windows Graphics Device Interface (GDI) by providing linear gradient and path gradient brushes for filling shapes, paths, and regions. Gradient brushes can also be used to draw lines, curves, and paths. When you fill a shape with a linear gradient brush, the color gradually changes as you move across the shape. For example, suppose you create a horizontal gradient brush by specifying blue at the left edge of a shape and green at the right edge. When you fill that shape with the horizontal gradient brush, it will gradually change from blue to green as you move from its left edge to its right edge. Similarly, a shape filled with a vertical gradient brush will change color as you move from top to bottom. The following illustration shows an ellipse filled with a horizontal gradient brush and a region filled with a diagonal gradient brush.

When you fill a shape with a path gradient brush, you have a variety of options for specifying how the colors change as you move from one portion of the shape to another. One option is to have a center color and a boundary color so that the pixels change gradually from one color to the other as you move from the middle of the shape towards the outer edges. The following illustration shows a path (created from a pair of Bézier splines) filled with a path gradient brush.

Cardinal Splines
GDI+ supports cardinal splines, which are not supported in GDI. A cardinal spline is a sequence of individual curves joined to form a larger curve. The spline is specified by an array of points and passes through each point in that array. A cardinal spline passes smoothly (no sharp corners) through each point in the array and thus is more refined than a path created by connecting straight lines. The following illustration shows two paths, one created by connecting straight lines and one created as a cardinal spline.

Independent Path Objects
In GDI, a path belongs to a device context, and the path is destroyed as it is drawn. With GDI+, drawing is performed by a Graphics object, and you can create and maintain several GraphicsPath objects that are separate from the Graphics object. A GraphicsPath object is not destroyed by the drawing action, so you can use the same GraphicsPath object to draw a path several times.

Transformations and the Matrix Object
GDI+ provides the Matrix object, a powerful tool that makes transformations (rotations, translations, and so on) easy and flexible. A matrix object works in conjunction with the objects that are transformed. For example, a GraphicsPath object has a Transform method that receives the address of a Matrix object as an argument. A single 3×3 matrix can store one transformation or a sequence of transformations. The following illustration shows a path before and after a sequence of two transformations (first scale, then rotate).

Scalable Regions
GDI+ expands greatly on GDI with its support for regions. In GDI, regions are stored in device coordinates, and the only transformation that can be applied to a region is a translation. GDI+ stores regions in world coordinates and allows a region to undergo any transformation (scaling, for example) that can be stored in a transformation matrix. The following illustration shows a region before and after a sequence of three transformations: scale, rotate, and translate.

Alpha Blending
Note that in the previous figure, you can see the untransformed region (filled with red) through the transformed region (filled with a hatch brush). This is made possible by alpha blending, which is supported by GDI+. With alpha blending, you can specify the transparency of a fill color. A transparent color is blended with the background color — the more transparent you make a fill color, the more the background shows through. The following illustration shows four ellipses that are filled with the same color (red) at different transparency levels.

Support for Multiple Image Formats
GDI+ provides the Image, Bitmap, and Metafile classes, which allow you to load, save and manipulate images in a variety of formats. The following formats are supported:
BMP
Graphics Interchange Format (GIF)
JPEG
Exif
PNG
TIFF
ICON
WMF
EMF

GDI Mapping Modes Explaind

2010-01-27T21:22:00.000-08:00

GDI Mapping Modes Explained

Date: 8 May 1997
Author: Rich Goldstein, MD (goldstei@interport.net)

NOTE: Also, take a look this article (http://www.bobpowell.net/mappingmodes.htm)

Overview

Each device context (DC, represented by TDC and derivatives in OWL) has the ability to maintain a coordinate system separate and distinct from the device it represents. So while the display may be a 640x480 or 800x600 or whatever pixels in dimension, we can tell the DC that the coordinate space uses some other units.

The result is the existence of 2 coordinate systems: the DEVICE coordinate system, and the LOGICAL coordinate system.

In general, DEVICE coordinates are established by the device or it's related drivers. So for the monitor, the display driver determines the DEVICE coordinates (0,0 in the top left, width,height in pixels in the lower right). These are rarely if ever changed programmatically (the exceptions, of course, include changing screen or printer resolution, or paper orientation, etc.).

The LOGICAL coordinates relate to the device context (DC) and are established by the mapping mode, viewport origin and extents, and window origin and extents. All DC related functions accept LOGICAL coordinates, unless explicitly stated (e.g. DPtoLP, which converts DEVICE coordinates to LOGICAL coordinates).

The system maps your LOGICAL coordinates to the DEVICE coordinates using the viewport/window origins and extents.

So WHAT ARE THEY, ALREADY???

Origins

OK, let's start with the window, which is expressed in LOGICAL coordinates.

SetWindowOrg() tells the DC the LOGICAL point that maps to the DEVICE point (0,0). So if you call SetWindowOrg(100,100) for a window, the LOGICAL point (100,100) occurs in the top left corner. (Hold on, this was the easy one...)

SetViewportOrg() tells the DC which DEVICE coordinate maps to LOGICAL point (0,0). So calling SetViewportOrg() with half the width and height of your window (in pixels), for example, sets the LOGICAL point (0,0) to the center of the window.

SetWindowOrg() and SetViewportOrg() can be called on any Mapping Mode. They serve to offset the origin of one system within the other. They have no effect on the relative distances specified by the two coordinate systems.

Mapping Modes

There are several mapping modes, some of which are constrained to a fixed relationship between DEVICE and LOGICAL coordinate systems.

Here is the list:

Name/Constant Constrained? Logical Unit
MM_TEXT (default) Yes Pixel
MM_LOENGLISH Yes 0.01 inch
MM_HIENGLISH Yes 0.001 inch
MM_LOMETRIC Yes 0.1 mm
MM_HIMETRIC Yes 0.01 mm
MM_TWIPS Yes 1/20 of a point, or 1/1440 of an inch
MM_ISOTROPIC No User Defined
MM_ANISOTROPIC No User Defined

For the 'constrained' modes, all you are allowed is to change the origin of the logical system using either SetWindowOrg or SetViewportOrg.

This means that if I set the mapping mode to MM_LOENGLISH, the point (0,0) and (0,100) are 1 inch apart (1 Logical inch, defined by the device capabilities, see GetDeviceCaps())

Extents

The extent is the maximum value of an axis. Extents are a little trickier, because how they are interpreted depends on the mapping mode. They are only appropriate for the non-constrained modes, MM_ISOTROPIC and MM_ANISOTROPIC.

The difference between these two modes is that MM_ISOTROPIC takes the parameters you pass to SetViewportExt and SetWindowExt as 'suggestions' (see below) and adjusts the extents so the the x and y axis coordinates represent the same distance on the device. This way, a LOGICAL unit in the x direction is the same length (in terms of the output) as a LOGICAL unit in the y direction (this is not intuitive... some printers may have different resolutions in the two axes... this mode ensures that the LOGICAL units are equivalent in space).

MM_ANISOTROPIC differs in that the parameters passed to SetViewportExt and SetWindowExt are taken literally. Windows make no adjustment. Therefore, you can have very different coordinate systems in the two axes.

SetWindowExt and SetViewportExt are used as a team. These two functions set some internal members in the DC, which are used to map points between coordinate systems. As such, each is essentially meaningless taken alone.

SetWindowExt tells the DC that a rectangle with the LOGICAL width and height passed in, has the DEVICE width and height passed in via SetViewportExt. Confused yet?

Let's say that I call SetViewportExt for a display device with the parameters 100,50. Taken alone, that's rather meaningless. Now I call SetWindowExt with parameters 100,100. This means that for each LOGICAL unit in the x direction, I will move 1 DEVICE unit. On the other hand, for each LOGICAL unit I move in the y direction, I move 1/2 a unit in the DEVICE coordinate.

These functions can also be called with negative numbers. When the sign of the parameters to SetWindowExt and SetViewportExt a different, the direction of the axes changes. So that the positive y direction can be up, instead of the usual default of down, if I call:
SetWindowExt(1,-1);
SetViewportExt(1,1);

One LOGICAL x unit translates to 1 DEVICE x unit, but 1 LOGICAL y unit translates to 1 DEVICE y unit, in the opposite direction.

Basically, here is the formula used (by Windows) to convert LOGICAL points to DEVICE points:

where xD = the DEVICE coordinate
and xL = the LOGICAL coordinate

xD = (xL - xWindowOrg)*(xViewportExt/xWindowExt) + xViewportOrg

If that makes anything clearer.
How Windows handles extents for MM_ISOTROPIC

Assuming that SetWindowExt is called BEFORE SetViewportExt (recommended), how the adjustments are made depends on the actual physical dimensions of the extents passed to SetViewportExt. Since device coordinates are not necessarily in equal units in the two axes, they are probably adjusted internally according to LOGPIXELSX/LOGPIXELSY.

If the physical dimensions of the Viewport Extents are wider than they are tall, the x extent is adjusted so that it's LOGICAL units are equal to the LOGICAL units for the y axis (as defined by the y parameters passed to SetWindowExt / SetViewportExt).

If the physical dimensions of the Viewport Extents are taller than they are wide, the y extent is adjusted.