回答

可以通过新建一个image对象来测试图片地址是否能正常打开，示例代码如下：

<script type="text/javascript">
    function testImage(url, timeoutT) {
        return new Promise(function (resolve, reject) {
            var timeout = timeoutT || 5000;
            var timer, img = new Image();
            img.onerror = img.onabort = function () {
                clearTimeout(timer);
                reject("error");
            };
            img.onload = function () {
                clearTimeout(timer);
                resolve("success");
            };
            timer = setTimeout(function () {
                // 这里可以替换成正确的图片地址
              
                img.src = "//!!!!/test.jpg";
                reject("timeout");
            }, timeout);
            img.src = url;
        });
    }
   
    testImage("//repo.bfw.wiki/bfwrepo/image/5d6539385ad28.png").then(res => {
            console.log(res);
        },err =>{
            console.log(err)
        });
    
</script>