webuploader插件 怎么设置头部 Access-Control-Allow-Origin？

Question

百度找的答案：
uploader.on('uploadBeforeSend', function(obj,data, headers) {
_.extend(headers, {
"Origin": http://localhost:3000 ,
"Access-Control-Request-Method":"POST"
});
});

然后报错 ： _ is no define

Answer 1

$.extend