Having problems with SetWindowText api

[bence.k]

Hello all!

I'm writing because I'm having some problems with the SetWindowText api
(Declare Function SetWindowText Lib "user32" Alias "SetWindowTextA "
(ByVal hwnd As Long, ByVal lpString As String) As Long)

I know the handle, and have the string what i want to see in the title.
Here is the code part:
c = SetWindowText(h wnd, "string")

c should be a double which is not null, it is ok because c returns a
good value every time
but after that
the window's caption should be "string", but it's became empty, not
"string".

i tried another way too. It is the SendMessage function.

we have the handle and the string again, and there is the code:
c = SendMessage(hwn d, 12, vbNull, "string")

c returns 1 so it should be ok
but the caption's text not ok again. it not empty but contains only one
character a Chr(8). if i replace the "string" with a vbNullString then
the caption text is empty again.

How can i set the right text in the caption?

Thanks,

Bence (iecs)

[Mattias Sjögren]

>I'm writing because I'm having some problems with the SetWindowText api

>(Declare Function SetWindowText Lib "user32" Alias "SetWindowTextA "
(ByVal hwnd As Long, ByVal lpString As String) As Long)

Make that

Declare Auto Function SetWindowText Lib "user32" (ByVal hwnd As
IntPtr, ByVal lpString As String) As Boolean
Mattias

--
Mattias Sjögren [C# MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

[Chris Dunaway]

be*****@gmail.c om wrote:

I'm writing because I'm having some problems with the SetWindowText api
(Declare Function SetWindowText Lib "user32" Alias "SetWindowTextA "
(ByVal hwnd As Long, ByVal lpString As String) As Long)

Your api declaration needs to be changed as Mattias already pointed
out. For additional information see here:

http://www.pinvoke.net/default.aspx/....SetWindowText