Javascript CORS 策略已阻止来自源“null”的请求：跨源请求
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from origin 'null' has been blocked by CORS policy: Cross origin requests
提问by index
This error occurred while calling up JSON. I don't know why this error is happening.
调用 JSON 时发生此错误。我不知道为什么会发生这个错误。
$.getJSON(url, function(data){
console.log(data);
});
Error:
错误：
Access to XMLHttpRequest at (this is JSON URL) from origin 'null' has been blocked by CORS policy: Cross origin requests are only supported for protocol schemes: http, data, chrome, chrome-extension, https.
回答by Ezekiel Victor
The error message says it all. You are apparently accessing the page running this script with a protocol scheme other than the several supported for cross-origin requests. This would happen commonly if you are, say, executing a local file in your browser via the file:// protocol and trying to access some URL on the Internet in your $.getJSONcall.
错误消息说明了一切。您显然正在使用除跨域请求支持的几种协议方案之外的协议方案访问运行此脚本的页面。例如，如果您通过 file:// 协议在浏览器中执行本地文件并尝试在$.getJSON通话中访问 Internet 上的某个 URL，则通常会发生这种情况。
