获取 JS 事件位置

• window.event.screenX (e4)
• window.event.screenY (e4)
• window.event.clientX (e4)
• window.event.clientY (e4)
• window.event.x (e4)
• window.event.y (e4)
• event.screenX (N4)
• event.screenY (N4)
• event.pageX (N4)
• event.pageY (N4)
• event.width (N4)
• event.height (N4)
• event.layerX (N4)
• event.layerY (N4)

  $("#btn1").click( function (event) {
alert(event.screenX );
        //......
  })