我建立执行HTTP请求到服务器的NodeJS但是当我执行HTTP请求的结果是下面的应用程序：
Access to XMLHttpRequest at 'http://127.0.0.1:8000/' from origin 'http://127.0.0.1:8080' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.
和
Uncaught (in promise) Error: XMLHttpRequest error.
dart:sdk_internal 41864:30 get current
package:http/src/packages/http/src/browser_client.dart 84:22 <fn>
dart:sdk_internal 99587:96 <fn>
at Object.dart.createErrorWithStack (dart_sdk.js:4617)
at Object.async._rethrow (dart_sdk.js:28723)
at async._AsyncCallbackEntry.new.callback (dart_sdk.js:28719)
at Object.async._microtaskLoop (dart_sdk.js:25352)
at async._startMicrotaskLoop (dart_sdk.js:25358)
at dart_sdk.js:25433
下面是我使用使用来进行HTTP请求的代码'package:http/http.dart' as http; ：
void requestGet(String endpoint, Callback cb) async {
return await http.get(Uri.encodeFull(url + endpoint),
headers: {"Accept": "application/json"}).then((http.Response response) {
print(response.body);
});
}
void requestPost(String endpoint, Map data, Callback cb) async {
return await http.post(Uri.encodeFull(url + endpoint),
body: data,
headers: {"Accept": "application/json"}).then((http.Response response) {
print(response.body);
});
}
