find lpClassName of started application to be used in FindWindow wniapi c++? - c++

Question

How can i find the lpClassName string of the FindWindow API call
if i start application with CreateProcess API function
PROCESS_INFORMATION ProcessInfo; //This is what we get as an [out] parameter
STARTUPINFO StartupInfo; //This is an [in] parameter
ZeroMemory(&StartupInfo, sizeof(StartupInfo));
StartupInfo.cb = sizeof StartupInfo ; //Only compulsory field
if(CreateProcess("c:\\temp\\application1.exe", NULL,
NULL,NULL,FALSE,0,NULL,
NULL,&StartupInfo,&ProcessInfo))
{
WaitForSingleObject(ProcessInfo.hProcess,INFINITE);
CloseHandle(ProcessInfo.hThread);
CloseHandle(ProcessInfo.hProcess);
}
else
{
MessageBox("The process could not be started...");
}
also can i some how set only part of the name in the FindWindow ?
for example if i know that allays the app name is "application< some version number>.exe"
so it can be :
application1.exe
application1.1.exe
application1.2.1.exe
my final goal is to use Windows Message system and the SendMessage API method to send messages to the application.

Answer 1

It sounds like what you really want is the handle to the window created by your launched application.
The problem is, your process might create many windows. You can use the SetWindowsHookEx function to be notified whenever the process creates a new window.
Untested code incoming:
LRESULT CALLBACK CBTProc(int nCode, WPARAM wParam, LPARAM lParam) {
if(nCode == HCBT_CREATEWND) {
// wParam is a handle to a window your app just created.
}
return 0;
}
CreateProcess("c:\\temp\\application1.exe", NULL,
NULL,NULL,FALSE,CREATE_SUSPENDED,NULL,
NULL,&StartupInfo,&ProcessInfo);
SetWindowsHookEx(WH_CBT, procHook, NULL, ProcessInfo.hThread);
ResumeThread(ProcessInfo.hTread);