char xitem[512];
char *pitem;
unsigned long pid;
HANDLE process;

HWND hwndLog=::FindWindowEx(NULL,NULL,NULL,"QQ");
HWND hwnd=::FindWindowEx(hwndLog,NULL,"Edit",NULL);
GetWindowThreadProcessId(hwndLog, &pid);
process=OpenProcess(PROCESS_VM_OPERATION|PROCESS_VM_READ|
PROCESS_VM_WRITE|PROCESS_QUERY_INFORMATION, FALSE, pid);

pitem=(char*)VirtualAllocEx(process, NULL, 512, MEM_COMMIT,
PAGE_READWRITE);

WriteProcessMemory(process, pitem, xitem, 512, NULL);
::SendMessage(hwnd, WM_GETTEXT, 512, (LPARAM)pitem);
//       ::SendMessage(hwnd, WM_GETTEXT, 512, (LPARAM)xitem);//这句是可以的。
ReadProcessMemory(process, pitem, xitem, 512, NULL); AfxMessageBox(xitem);

VirtualFreeEx(process, pitem, 0, MEM_RELEASE);