As you're generating the image dynamically, set the onload property before the src . var img = new Image(); img.onload = function ... ... <看更多>

The image's load event · First, create an image element after the document has been fully loaded by place the code inside the event handler of the window's load ... ... <看更多>

(function(){. var loc = document.location.search,. t = new Date(),. img = new Image(),. src = '';. if(loc.indexOf('page=hoge') > -1){. ... <看更多>

在之前的Promise应用场景与模块化尝试一文中提到过，图片加载之前用img.complete作为判断来决定是否异步加载图片，但是img.complete并不是特别靠谱的 ... ... <看更多>