image.onload()或image.addEventListener()无法在Safari中运行,任何解决方案?

时间:2016-03-01 09:35:45

标签: javascript jquery safari closures onload-event

我试图让它在过去的两天里工作,浏览了我遇到的关于这个问题的每篇文章,但我似乎无法在Safari中使它工作。代码在Firefox和Chrome中完美运行,但是当我在Safari中测试时,它总是令我失望。我正在尝试执行以下操作:

for (var j = 0; j < total_reports; j++) {
        var svgString = $(elem_graph).find('svg');
        $(svgString)[0].setAttribute('width','2500');
        $(svgString)[0].setAttribute('height','500');
        $(svgString)[0].setAttribute('viewBox', '0 0 1000 200');
        $(svgString)[0].setAttribute('preserveAspectRatio', 'none');


        $(elem_graph).find("span").html();
        var img = new Image();
        var DOMURL = self.URL || self.webkitURL || self;
        var svg = new Blob([svgString], {type: "image/svg+xml;charset=utf-8"});
        var url = DOMURL.createObjectURL(svg);

        var svgString = $(elem_graph).find('svg');
        $(svgString)[0].setAttribute('width','2500');
        $(svgString)[0].setAttribute('height','500');
        $(svgString)[0].setAttribute('viewBox', '0 0 1000 200');
        $(svgString)[0].setAttribute('preserveAspectRatio', 'none');
        svgString=$(elem_graph).find("span").html();

        var DOMURL = self.URL || self.webkitURL || self;
        var svg = new Blob([svgString], {type: "image/svg+xml;charset=utf-8"});
        var url = DOMURL.createObjectURL(svg);
        img.onload = (function(img) {
            return function() {
                var canvas = document.getElementById("canvas");
                var ctx = canvas.getContext("2d");
                ctx.drawImage(img, 0, 0);
                var png = canvas.toDataURL("image/png");

                pdf.addImage(png, 'PNG', 10, 120, 485, 270);
                pdf.addPage();
                DOMURL.revokeObjectURL(png);
                pdf.save("test.pdf");

                img_load_counter++;
                canvas = null;
                ctx = null;
                png = null;
            }
        })(img);
        img.src = url;
        svgString = null;
    svg=null;
    unformatSvgString = null;
    url=null;
    }

它工作正常,直到它达到“img.onload =(function(img)”它只是没有为img注册load事件。我也尝试了addEventListener()但它似乎也没有工作。

此外,闭包,“canvas = null;                     ctx = null;                     png = null;“似乎根本不释放任何内存,也欢迎任何解决方案。

1 个答案:

答案 0 :(得分:0)

也许为时已晚,但我希望它对其他人有帮助。 您可以更改:

    var DOMURL = self.URL || self.webkitURL || self;
    var svg = new Blob([svgString], {type: "image/svg+xml;charset=utf-8"});
    var url = DOMURL.createObjectURL(svg);

具有:

url = "data:image/svg+xml;charset=utf-8," + encodeURIComponent( svgString );