nodejs asios 获取图片二进制 js读取图片blob

1 function getimage(imageurl){
 2 　　var arr = imageurl.split('/');
 3　　function binaryToArrayBuffer(data) {
 4    　　var arr = new Uint8Array(data.length);
 5       for(var i = 0, l = data.length; i < l; i++) {
 6       　　arr[i] = data.charCodeAt(i);
 7       }
10      return arr.buffer;
12   };
13                     //获取原始responseTest并转化为arrayBuffer格式
14   function getImageArrBuffer(url) {
15       var r = new XMLHttpRequest();
16       r.open("GET", url, false);
17       r.overrideMimeType('text/plain; charset=x-user-defined');
18       r.send(null);
19       var arrayBuffer = binaryToArrayBuffer(r.responseText);
20       arrayBuffer.name = arrayBuffer.fileName = url.substring(url.lastIndexOf('/') + 1);
21       arrayBuffer.fileType = "image/jpeg"; //"image/octet-stream";
22           return arrayBuffer;
23   };
24       var response = getImageArrBuffer(imageurl);
25          console.log(response);26 }