PostThreadMessage in c#

[sulabh120881]

Hi,


I am using PostThreadMessage() for sending data from my main form to a thread.
and receiving with GetMessage()


[DllImport("coredll.dll")]
public static extern bool PostThreadMessage(int threadId, uint msg, ushort wParam, uint lParam);

[DllImport("coredll.dll")]
public static extern int GetMessage(ref MSG msg, IntPtr hwnd, ushort fMin, uint fMax);


if I send msg in interger format then I am able to get the data.


But I want to send/recv data in structure format only.
Can anybody tell me how this can be done in c#


Thanks in advance

[VictorN]

What did you mean by this:if I send msg in interger format then I am able to get the data.

But I want to send/recv data in structure format only.
:confused:

[sulabh120881]

Hi,


Here I want to say

in PostThreadMessage(int threadId, uint msg, ushort wParam, uint lParam);

if I send msg = 10, lParam = 20, I can see the data in GetMessage's MSG structure.


But if I want to send some string value how I can send it.


I tried it

string s = "bob";
char[] buff = new char[100];
s.CopyTo(0, buff, 0, s.Length);

unsafe
{
fixed (char* pbuff = buff) postit((uint)pbuff);
}

where postit is

PostThreadMessage(idthread, 11, 0, buff);


but not able to recv this string with GetMessage()

[MikeAThon]

Are you using PostThreadMessage across different processes, or merely between threads of the same process? If you are posting across different processes, then since each process has its own memory, one process will not be able to see the memory content of another.

You might want to consider the WM_COPYDATA message if posting between different processes: http://msdn.microsoft.com/en-us/library/ms649011(v=vs.85).aspx

Incidentally, use of PostThreadMessage is definitely BAD if the target thread has any visible UI. If the UI of the target thread is being manipulated by the user, then the posted message will be LOST: "PRB: PostThreadMessage Messages Lost When Posted to UI Thread" at http://support.microsoft.com/kb/183116

Mike

[Arjay]

In C#, there's no need to call postthreadmessage. Instead use the builtin threading functionality of C#.

Like backgroundworker class. Also check out InvokeRequired property.