ajax请求清除缓存

src/js/promise.js

@@ -44,6 +44,10 @@ const post = function(url,data){
       url:url,
       data:JSON.stringify(data),
       contentType:"application/json; charset=UTF-8",
+      beforeSend :function(xmlHttp){
+        xmlHttp.setRequestHeader("If-Modified-Since","0");
+        xmlHttp.setRequestHeader("Cache-Control","no-cache");
+      },
       success:function(res){
         resolve({data:res});
       },