jQuery ajax 发布请求是请求的资源上不存在“Access-Control-Allow-Origin”标头。
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ajax post request is No 'Access-Control-Allow-Origin' header is present on the requested resource.'
提问by harishkumar329
I'm just making an ajax post request and I'm getting an error like:
我只是在发出一个 ajax 发布请求，但出现了如下错误：
XMLHttpRequest cannot load https://xxx.com?redirect_uri=http://www.example.com. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://example.com' is therefore not allowed access.
XMLHttpRequest 无法加载 https://xxx.com?redirect_uri=http://www.example.com。请求的资源上不存在“Access-Control-Allow-Origin”标头。因此不允许访问源“http://example.com”。
And here I can see there is nothing different from my response domain and request domain except "www", so does "www" also cause this issue?
在这里我可以看到除了“www”之外，我的响应域和请求域没有什么不同，那么“www”是否也会导致这个问题？
回答by Rory McCrossan
The problem is because you are making a cross-domain AJAX request, which prevented by browser security - see the Same Origin Policy.
问题是因为您正在发出跨域 AJAX 请求，而浏览器安全性阻止了该请求 - 请参阅Same Origin Policy。
The request is expecting you to be making a request to a CORS enabled domain, hence why it is complaining about the non-existant header.
该请求期望您向启用 CORS 的域发出请求，因此它抱怨不存在的标头。
You either need to change your request to jsonptype, or use a server-side proxy to get the data.
您要么需要更改请求jsonp类型，要么使用服务器端代理来获取数据。
回答by Sydney Collins
When requesting data from external website it is always best to not do it in ajax , but if you have to do it an ajax have a internal page which makes a call with server side code and call that page with ajax.
当从外部网站请求数据时，最好不要在 ajax 中进行，但如果你必须这样做，ajax 有一个内部页面，它使用服务器端代码进行调用并使用 ajax 调用该页面。
