整理文档，搜刮出一个js实现canvas保存图片为png格式并下载到本地的方法，稍微整理精简一下做下分享。
1.canvas 保存图片
2.下载到本地
function base64Img2Blob(code){ var parts = code.split(';base64,'); var contentType = parts[0].split(':')[1]; var raw = window.atob(parts[1]); var rawLength = raw.length; var uInt8Array = new Uint8Array(rawLength); for (var i = 0; i < rawLength; ++i) { uInt8Array[i] = raw.charCodeAt(i); } return new Blob([uInt8Array], {type: contentType}); } function downloadFile(fileName, content){ var aLink = document.createElement('a'); var blob = base64Img2Blob(content); //new Blob([content]); var evt = document.createEvent("HTMLEvents"); evt.initEvent("click", false, false);//initEvent 不加后两个参数在FF下会报错 aLink.download = fileName; aLink.href = URL.createObjectURL(blob); aLink.dispatchEvent(evt); } downloadFile('ship.png', canvas.toDataURL("image/png"));