每日一个js实例15--canvas绘图内容打印

 <a href="javascript:void(0)" id="print">打印</a>

<h3>不被打印区域</h3>
 <canvas width="500" height="400" id="canvas1"></canvas>

<script type="text/javascript">   

   function fun(id){return document.getElementById(id);}

    var canvas=fun("canvas1");

    var c=canvas.getContext("2d");

    c.fillRect(100,100,200,200);

  //IE不支持dataURL函数不兼容IE，因此本打印只支持Eedge/谷歌/火狐

  fun("print").onclick=function(){

    var dataURL = canvas.toDataURL("image/png");

    var newWindow=window.open();

    newWindow.document.write('<img src="'+dataURL+'"/>');

    newWindow.print();

 }

</script>