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1、假如访问的接口地址为 http://www.test.com/apis/index.php （php api 接口）
2、而开发地址为http://127.0.0.1:8080,当axios发起请求时，出现如下错误：
Failed to load http://www.test.com/apis/index.php?&act=login: The value of the 'Access-Control-Allow-Origin' headerin the response must not be the wildcard '*' when the request's credentials mode is 'include'. Origin 'http://127.0.0.1:8080' is therefore not allowed access. The credentials mode of requests initiated by the XMLHttpRequest is controlled by the withCredentials attribute.