如何在HTML5中将画布数据保存到文件中？

<canvas id = &rdquo;canvas1&rdquo; width = &rdquo;250&rdquo; height = &rdquo;150&rdquo;></canvas>                                 

var canvas = document.getElementById("Canvas1"); var ctx1 = canvas.getContext("2d");ctx1.moveTo(0,0); ctx1.lineTo(300,200); ctx1.stroke(); // This method actually draw graphics as per context object             

var imgurl= canvas.toDataURL( ) ; / / This method saves graphics in pngdocument.getElementById(‘cimg’).src = imgurl; // This will set img src to dataurl(png)so that it can be saved as image.