How to check the mouse button state

 

 

A computer mouse is an input pointing device which having two buttons, known as Left & Right buttons. These buttons clicks primary source of events in the Windows Programming model. How can we check whether the mouse button is pressed or not from our application on a particular event.

 

 

Windows API provides GetKeyState function to retrieves the status of a specified virtual key. That means we have to use VK_LBUTTON or VK_RBUTTON, which are the virtual keys corresponding to the mouse L and R buttons. If the high order bit is 1, the key is down, otherwise key is up. Actually the return value of this function specifies the status of the given virtual key.

 

 

void CheckMouseButtonStatus()
{
   //Check the mouse left button is pressed or not
   if ((GetKeyState(VK_LBUTTON) & 0x80) != 0)
   {
      AfxMessageBox(_T("LButton pressed"));
   }
   //Check the mouse right button is pressed or not
   if ((GetKeyState(VK_RBUTTON) & 0x80) != 0)
   {
      AfxMessageBox(_T("RButton pressed"));
   }
}

 

 

Check the GetAsyncKeyState function too in the MSDN.