Detect if mouse button is down

Question

I am new to c++ and I am trying to activate a line of code only when the left mouse button is held down. In this example, my code works but it seems that it just toggles it. When I click, it spams the H key then, when I click again, it stops.

Currently I have this code:

if ((GetKeyState(VK_LBUTTON)))
{
    keybd_event(VkKeyScan('H'),0,0,0);
    Sleep ( 30 );
}

Edit:

I have inside the function:

int WINAPI WinMain ( HINSTANCE hInst, HINSTANCE P, LPSTR CMD, int nShowCmd );

Answer 1

Use this to determine if the button is pressed.

if((GetKeyState(VK_LBUTTON) & 0x8000) != 0)

http://vcpptips.wordpress.com/tag/vk_lbutton/

Answer 2

The application can catch messages and process being sent to your window indicating a state change of any mouse button.

When the left button is pressed a

WM_LBUTTONDOWN

is sent.

When it is released

WM_LBUTTONUP

is sent.

Please read here for various messages being sent to indicate mouse events.