我一直在四处寻找如何使用 http 包及其 http.post() 方法访问和创建 Cloud Firestore 集合中的新文档 - 但似乎我遇到的所有文章都是 2019 年及之前的.无论我尝试什么，我都会不断收到以下错误:

Error: XMLHttpRequest error.
    dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/errors.dart 264:20      get current
packages/http/src/browser_client.dart 84:22                                       <fn>
dart-sdk/lib/async/zone.dart 1450:54                                              runUnary
dart-sdk/lib/async/future_impl.dart 143:18                                        handleValue
dart-sdk/lib/async/future_impl.dart 696:44                                        handleValueCallback
dart-sdk/lib/async/future_impl.dart 725:32                                        _propagateToListeners
dart-sdk/lib/async/future_impl.dart 519:7                                         [_complete]
dart-sdk/lib/async/stream_pipe.dart 61:11                                         _cancelAndValue
dart-sdk/lib/async/stream.dart 1300:7                                             <fn>
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 324:14  _checkAndCall
dart-sdk/lib/_internal/js_dev_runtime/private/ddc_runtime/operations.dart 329:39  dcall
dart-sdk/lib/html/dart2js/html_dart2js.dart 37275:58                              <fn>


    at Object.createErrorWithStack (http://localhost:49938/dart_sdk.js:4342:12)
    at Object._rethrow (http://localhost:49938/dart_sdk.js:37882:16)
    at async._AsyncCallbackEntry.new.callback (http://localhost:49938/dart_sdk.js:37876:13)
    at Object._microtaskLoop (http://localhost:49938/dart_sdk.js:37708:13)
    at _startMicrotaskLoop (http://localhost:49938/dart_sdk.js:37714:13)
    at http://localhost:49938/dart_sdk.js:33226:9
Application finished.

我在 Flutter 中的代码:

  Future<http.Response> _post() {
   
    String url =
        'https://firestore.googleapis.com/v1/projects/onebear-webapp/databases/(default)/collections/txt?key=AIzxSyAllNuEbN40DEvBPIQkcLIWn00c9TYWqY';
    return http.post(
      url,
      headers: <String, String>{
        'Content-Type': 'application/json; charset=UTF-8',
      },
      body: jsonEncode(<String, String>{
        'title': 'title',
      }),
    );
  }

我已阅读有关 CORS 的信息并尝试从 codewithandrea.com ( https://codewithandrea.com/videos/2020-05-25-top-8-tips-for-flutter-web-firebase/ ) 获取解决方案 - 仍然没有成功

感谢任何建议和指导，以使其发挥作用。

最佳答案

将其放在 header 参数中。

headers: {
  "Access-Control-Allow-Origin": "*", // Required for CORS support to work
  "Access-Control-Allow-Credentials": true, // Required for cookies, authorization headers with HTTPS
  "Access-Control-Allow-Headers": "Origin,Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Amz-Security-Token",
  "Access-Control-Allow-Methods": "POST, OPTIONS"
},
body: JSON.stringify(item);

关于firebase - 使用带有 Flutter Web App 的 http 包发布到 Cloud Firestore 及其 REST API，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/64226729/