#define MOUSEEVENTF_MOVE 0x0001 /* mouse move */ #define MOUSEEVENTF_LEFTDOWN 0x0002 /* left button down */ #define MOUSEEVENTF_LEFTUP 0x0004 /* left button up */ #define MOUSEEVENTF_RIGHTDOWN 0x0008 /* right button down */ #define MOUSEEVENTF_RIGHTUP 0x0010 /* right button up */ #define MOUSEEVENTF_MIDDLEDOWN 0x0020 /* middle button down */ #define MOUSEEVENTF_MIDDLEUP 0x0040 /* middle button up */ #define MOUSEEVENTF_WHEEL 0x0800 /* wheel button rolled */ #define MOUSEEVENTF_ABSOLUTE 0x8000 /* absolute move */The virtual keycodes (VK_) can also be found there.