1  <HTML>
  2  
  3  <HEAD>
  4  
  5    <TITLE>JavaScript Event Object</TITLE>
  6  
  7    <SCRIPT LANGUAGE="JavaScript1.2">
  8  
  9    // Handle a mouse event:
 10    function mouseHandler( e ) {
 11      var msg = "Event type: " + e.type;
 12      msg += "\nX position: " + e.layerX;
 13      msg += "\nY position: " + e.layerY;
 14      msg += modifierMsg( e );
 15      alert( msg );
 16      return false;
 17    }
 18  
 19    // Return a message describing the modifier 
 20    // keys held down:
 21    function modifierMsg( e ) {
 22      var msg = "";
 23      if ( isAlt( e ) ) 
 24        msg += "\nAlt key was down.";
 25      if ( isControl( e ) ) 
 26        msg += "\nControl key was down.";
 27      if ( isShift( e ) ) 
 28        msg += "\nShift key was down.";
 29      // What key is the meta-key?
 30      if ( isMeta( e ) ) 
 31        msg += "\nMeta key was down.";
 32      return msg;
 33    }
 34    
 35    function isAlt( e ) {
 36      return e.modifiers & Event.ALT_MASK;
 37    }
 38    function isControl( e ) {
 39      return e.modifiers & Event.CONTROL_MASK;
 40    }
 41    function isShift( e ) {
 42      return e.modifiers & Event.SHIFT_MASK;
 43    }
 44    function isMeta( e ) {
 45      return e.modifiers & Event.META_MASK;
 46    }
 47  
 48    window.captureEvents( Event.MOUSEDOWN );
 49    
 50    /*  
 51     *  In JavaScript 1.1, event handlers *must* be written
 52     *  in lowercase (as below).  Here it doesn't matter,
 53     *  however, since this script requires JavaScript 1.2.
 54     */
 55    
 56    window.onmousedown = mouseHandler;
 57  
 58    </SCRIPT>
 59  
 60  </HEAD>
 61  
 62  <BODY BGCOLOR="#FFFFFF">
 63  
 64    Click the mouse anywhere in this browser window.<BR>
 65    Optionally hold down Ctl, Alt, and/or Shift as you click.
 66  
 67  </BODY>
 68  
 69  </HTML>
 70