如何确定是否按下了鼠标左键？

Question

In a winform, the form will follow the mouse when the mouse is down, but sometimes when the machine particularly is slow, the form is following the mouse even the mouse is out, so I used win32 dll to judge the state of the mouse

 [DllImport("user32.dll")]
    static extern short GetAsyncKeyState(int nVirtKey);
    public static bool GetCurrentLeftMouseIsDowning()
    {
        if (GetAsyncKeyState(0x01) == 0)
            return false;
        else
            return true;
    }

But the memory will increase when the form has been dragging, and what other way to determine the state of the mouse?Or how to control the memory when the form is dragged？？

Answer 1

Considering you are using winform, you can use form1_mousedown event for this

refer this