canvas转图片自动下载本地、并且重命名的解决方法

//canvas图像base64转码
 var d=canvas.toDataURL("image/jpeg",0).replace("image/jpeg", "image/octet-stream;");

//自动下载
function saveFile(data, filename) {
				var save_link = document.createElementNS('http://www.w3.org/1999/xhtml', 'a');
				save_link.href = data;
				save_link.download = filename;
				var event = document.createEvent('MouseEvents');
				event.initMouseEvent('click', true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null);
				save_link.dispatchEvent(event);
			};

saveFile(d,"test.jpg");