1 transformFile: function(file, done) {
2 //如果不超过2M直接上传
3 if (file.size < 2048 * 1000) return done(file);
4
5 //这里的File对象继承自Blob,
6 //当执行到这里的时候File不一定加载完
7 //所以需要再加载一次,回调中进行压缩
8 var reader = new FileReader();
9 reader.addEventListener("loadend",
10 function() {
11 // 压缩图片大小
12 var img = new Image();
13 img.onload = function() {
14 var cvs = document.createElement('canvas');
15 cvs.width = img.naturalWidth;
16 cvs.height = img.naturalHeight;
17
18 var ctx = cvs.getContext("2d").drawImage(img, 0, 0);
19
20 var zipImg = cvs.toDataURL("image/jpeg", 70 / 100);
21 console.log(zipImg);
22 return done(Dropzone.dataURItoBlob(zipImg));
23 };
24 img.src = reader.result;
25 });
26 reader.readAsDataURL(file);
27 }
