翻翻过去那场雪
config配置文件中有两个参数// onUploadProgress: function(progressEvent) {// // Do whatever you want with the native progress event// },// onDownloadProgress: function(progressEvent) {// // Do whatever you want with the native progress event// },分别处理上传和下载事件,也就是这里绑定了upload事件,所以每次请求都会有个option请求。