Question

vc++ SendMessage和WM_SETTEXT问题.

void CFsaDlg::OnButton1()
{
HWND hwnd,Ahwnd;
hwnd=::FindWindow(NULL,"Form1");
Ahwnd=::FindWindowEx(hwnd,0,"ThunderRT6TextBox","");
CString s;
s="呵呵";
::SendMessage(Ahwnd,WM_SETTEXT,s,0);
}

hwnd,Ahwnd都能成功获得句柄.

D:\Microsoft Visual Studio 6\MyProjects\fsa\fsaDlg.cpp(184) : error C2664: 'SendMessageA' : cannot convert parameter 3 from 'class CString' to 'unsigned int'
void CFsaDlg::OnButton1()
{
HWND hwnd,Ahwnd;
hwnd=::FindWindow(NULL,"Form1");
Ahwnd=::FindWindowEx(hwnd,0,"ThunderRT6TextBox","");
::SendMessage(Ahwnd,WM_SETTEXT,0,LPARAM("呵呵"));
}

Answer 1

::SendMessage(Ahwnd,WM_SETTEXT,0,_T("hehe"));

参数错啦~第三个参数无用, 第四个才是c字符串~
wParam
This parameter is not used.
lParam
Pointer to a null-terminated string that is the window text.