canvas使用toDataUrl()出错,img设置img.crossOrigin = "*"也没用。

页面要做一个截图的功能,本地生成了一张图片,然后转成canvas,再从canvas变成png,但是canvas.toDataUrl()一直报错:

Uncaught DOMException: Failed to execute 'toDataURL' on 'HTMLCanvasElement': Tainted canvases may not be exported.

代码如下:

var url = DOMURL.createObjectURL(svg);
        var canvas = document.createElement('canvas');
        var ctx = canvas.getContext('2d');
        canvas.width = window.innerWidth;
        canvas.height = window.innerHeight*1.25;
        cacheImg(url,function(){
            ctx.drawImage(this , 0 , 0);
            var image = canvas.toDataURL("image/png").replace("image/png", 'image/octet-stream');
            DOMURL.revokeObjectURL(url);
        });
        
        function cacheImg(url , callback){
            var img = new Image()
            img.setAttribute('crossOrigin', 'Anonymous');
            img.src = url;
            img.onload = function() {
                callback.call(img)
            }
        }
阅读 21.2k
1 个回答
撰写回答
你尚未登录,登录后可以
  • 和开发者交流问题的细节
  • 关注并接收问题和回答的更新提醒
  • 参与内容的编辑和改进,让解决方法与时俱进
推荐问题