IE7 检测画布上鼠标点击坐标

Question

canvas.onmousedown=function(e){
     alert("e.offsetX: "+e.offsetX);
         var stX=e.layerX-10;
 var stY=e.layerY-10;
 alert("stX:  "+stX);
     if(stX>x1&&stX<x1+w1&&stY>y1&&stY<y1+h1)
 {
    alert("click pic_1");
angle1+=45;
 }
         
            draw();
            }

Answer 1

相关代码段如上，是不是IE7不支持e.offsetX或者e.layerX属性？那应该怎样检测mousedown的坐标？

Answer 2

canvas.onmousedown=function(e){
var e = e || window.event
                     alert("e.offsetX: "+e.offsetX);
                         var stX=e.layerX-10;
                     var stY=e.layerY-10;
                     alert("stX:  "+stX);
                     if(stX>x1&&stX<x1+w1&&stY>y1&&stY<y1+h1)
                     {
                        alert("click pic_1");
                        angle1+=45;
                     }
                     
                        draw();
                        }
不是不支持offsetX/Y 而是event对象 是保存在window下的