How to get mouse events from outside of program window

问题

I want to drag this character. Image :

so i use this method to get mouse position:

WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    ...
    switch (message){
    case WM_LBUTTONDOWN:
    case WM_MOUSEMOVE:
        GetCursorPos(&mousePosition);
        break;
    }
    ...
}

The program seems to be running well, but if the mouse is out of the characters location, it wouldn't follow the mouse cursor anymore.

How can I fix this problem?

回答1:

See SetCapture on MSDN:

Sets the mouse capture to the specified window belonging to the current thread. SetCapture captures mouse input either when the mouse is over the capturing window, or when the mouse button was pressed while the mouse was over the capturing window and the button is still down. Only one window at a time can capture the mouse.

SetCapture..ReleaseCapture lets you temporarily extend your mouse event handling to space outside the window [where the event originated from].

You have some sample/demo here:

switch (uMsg) 
{ 
   case WM_LBUTTONDOWN: 

        // Capture mouse input. 
        SetCapture(hwndMain); // <<--- Here we go

来源：https://stackoverflow.com/questions/23442725/how-to-get-mouse-events-from-outside-of-program-window