浏览器用jq发送put/delete请求怎么解决 400 请求报错 

代码如下         lostDelete:function(lostId){             var a;             var keywords={"tokenId":sessionStorage.getItem("tokenIdSave"),                     "userId":sessionStorage.getItem("userIdSave"),                     "id":location.hash.substr(1)};                     console.log(keywords);              $.ajax({                 type:"DELETE",//http://192.168.0.88:8080                     url:"http://192.168.0.88:8080/api/app/losts/"+location.hash.substr(1)+"/delete",                 data:keywords,                 contentType:"application/json",                 dataType:"json",                 async:false,                 success: function (res) {                     console.log(res)                 },                 error: function () {                    console.log("error")                 }            });         } 我的代码就是这样  而且服务器端加了允许跨域的设置了，但是还是这样报错

jquery.js:9631 XMLHttpRequest cannot load http://192.168.0.88:8080/api/app/losts/cf6535f53b674c8e96105f7536a167b2/delete. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://127.0.0.1:8020' is therefore not allowed access. send @ jquery.js:9631 ajax @ jquery.js:9176 lostDelete @ lostsXiangxi.html:542 (anonymous) @ lostsXiangxi.html:683 dispatch @ jquery.js:4641 jQuery.event.add.elemData.handle @ jquery.js:4309 lostsXiangxi.html:555 error 求解答