主要思想是借助Canvas自己的API - toDataURL()來實現，整個實現 HTML + JavaScript的代碼很簡單。
復制代碼代碼如下: html meta http-equiv="X-UA-Compatible" content="chrome=1" head script window.onload = function() { draw(); var saveButton = document.getElementById("saveImageBtn"); bindButtonEvent(saveButton, "click", saveImageInfo); var dlButton = document.getElementById("downloadImageBtn"); bindButtonEvent(dlButton, "click", saveAsLocalImage); }; function draw(){ var canvas = document.getElementById("thecanvas"); var ctx = canvas.getContext("2d"); ctx.fillStyle = "rgba(125, 46, 138, 0.5)"; ctx.fillRect(25,25,100,100); ctx.fillStyle = "rgba( 0, 146, 38, 0.5)"; ctx.fillRect(58, 74, 125, 100); ctx.fillStyle = "rgba( 0, 0, 0, 1)"; // black color ctx.fillText("Gloomyfish - Demo", 50, 50); } function bindButtonEvent(element, type, handler) { if(element.addEventListener) { element.addEventListener(type, handler, false); } else { element.attachEvent('on'+type, handler); } } function saveImageInfo () { var mycanvas = document.getElementById("thecanvas"); var image = mycanvas.toDataURL("image/png"); var w=window.open('about:blank','image from canvas'); w.document.write(" img src='"+image+"' alt='from canvas'/ } function saveAsLocalImage () { var myCanvas = document.getElementById("thecanvas"); // here is the most important part because if you dont replace you will get a DOM 18 exception. // var image = myCanvas.toDataURL("image/png").replace("image/png", "image/octet-stream;Content-Disposition: attachment;filename=foobar.png"); var image = myCanvas.toDataURL("image/png").replace("image/png", "image/octet-stream"); window.location.href=image; // it will save locally } /script /head body bgcolor="#E6E6FA" div canvas width=200 height=200 id="thecanvas" /canvas button id="saveImageBtn" Save Image /button button id="downloadImageBtn" Download Image /button /div /body /html
