如何允许跨源资源共享？(how do I allow cross origin resource sharing? [duplicate])

 
 
 这个问题在这里已有答案： 
 
 
 
  
 CORS＆example.com 3个答案 
 
 
 
 
 我不知道为什么我的ajax CORS不起作用.. 
 
 阿贾克斯 
 
 $(document).ready(function(){  
        var xhr = new XMLHttpRequest();
        $.ajax({
            url: "SERVER_URL_AND_PARAMETERS",
            type:"POST",
            beforeSend:function(xhr){
                xhr.setRequestHeader("Access-Control-Allow-Origin", "*");
                xhr.setRequestHeader("Access-Control-Allow-Methods", "GET, POST");
            },
            dataType:"json",
            crossDomain: true,
            success:function(data, textStatus, xhr){
                alert(data);
            },
            error:function(xhr,status,error){
                alert("code:"+xhr.textStatus+"\n"+"message:"+error.responseText+"\n"+"error:"+error.log); 

            }

        });

    });
 
 响应标头 
 
 Allow:GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS
    Cache-Control:no-cache="set-cookie, set-cookie2"
    Connection:Keep-Alive
    Content-Language:ko-KR
    Content-Length:0
    Content-Type:text/plain
    Date:Mon, 02 Nov 2015 07:19:54 GMT
    Expires:Thu, 01 Dec 1994 16:00:00 GMT
    Keep-Alive:timeout=10, max=100
    Set-Cookie:SOME_COOKIES; Expires=Tue, 01-Nov-16 07:19:53 GMT; Path=/
    X-UA-Compatible:IE=EmulateIE8, requiresActiveX=true
 
 请求标头 
 
Accept:*/*
Accept-Encoding:gzip, deflate, sdch
Accept-Language:en-US,en;q=0.8
Access-Control-Request-Headers:accept, access-control-allow-headers, access-control-allow-methods, access-control-allow-origin
Access-Control-Request-Method:POST
Connection:keep-alive
Host:SERVER_URL
Origin:http://CLIENT_URL
Referer:http://CLIENT_URL/AND/JSP_FILE_PATH.jsp?lineCd=CODE1&prdtCode=CODE2
User-Agent:Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.80 Safari/537.36
 
 铬错误细节 
 
MLHttpRequest cannot load SERVER_URL_AND_PARAMETER Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'CLIENT_URL' is therefore not allowed access.
 
 我不知道我的代码有什么问题。 我正在开发CLIENT_URL端Web应用程序。 

 
 
This question already has an answer here:
 
 
 
  
 CORS & example.com  3 answers  
 
 
 
 
I don't know why my ajax CORS doesn't work..
 
ajax 
 
 $(document).ready(function(){  
        var xhr = new XMLHttpRequest();
        $.ajax({
            url: "SERVER_URL_AND_PARAMETERS",
            type:"POST",
            beforeSend:function(xhr){
                xhr.setRequestHeader("Access-Control-Allow-Origin", "*");
                xhr.setRequestHeader("Access-Control-Allow-Methods", "GET, POST");
            },
            dataType:"json",
            crossDomain: true,
            success:function(data, textStatus, xhr){
                alert(data);
            },
            error:function(xhr,status,error){
                alert("code:"+xhr.textStatus+"\n"+"message:"+error.responseText+"\n"+"error:"+error.log); 

            }

        });

    });
 
response headers
 
 Allow:GET, HEAD, POST, PUT, DELETE, TRACE, OPTIONS
    Cache-Control:no-cache="set-cookie, set-cookie2"
    Connection:Keep-Alive
    Content-Language:ko-KR
    Content-Length:0
    Content-Type:text/plain
    Date:Mon, 02 Nov 2015 07:19:54 GMT
    Expires:Thu, 01 Dec 1994 16:00:00 GMT
    Keep-Alive:timeout=10, max=100
    Set-Cookie:SOME_COOKIES; Expires=Tue, 01-Nov-16 07:19:53 GMT; Path=/
    X-UA-Compatible:IE=EmulateIE8, requiresActiveX=true
 
request headers
 
Accept:*/*
Accept-Encoding:gzip, deflate, sdch
Accept-Language:en-US,en;q=0.8
Access-Control-Request-Headers:accept, access-control-allow-headers, access-control-allow-methods, access-control-allow-origin
Access-Control-Request-Method:POST
Connection:keep-alive
Host:SERVER_URL
Origin:http://CLIENT_URL
Referer:http://CLIENT_URL/AND/JSP_FILE_PATH.jsp?lineCd=CODE1&prdtCode=CODE2
User-Agent:Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.80 Safari/537.36
 
chrome error detail
 
MLHttpRequest cannot load SERVER_URL_AND_PARAMETER Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'CLIENT_URL' is therefore not allowed access.
 
I don't know what is the problem on my code. I am working on CLIENT_URL side web application. 

原文：https://stackoverflow.com/questions/33472731