javascript - 没有导出成员 'Headers' 和 RequestOptions

Question

https://www.techiediaries.com/ionic-http-post/

我正在遵循本教程。运行 ionicserve 时出现以下错误

ng] ERROR in src/app/home/home.page.ts:2:22 - error TS2305: Module '"../../../node_modules/@angular/common/http"' has no exported member 'Headers'.
[ng] 2 import { HttpClient, Headers, RequestOptions } from '@angular/common/http';
[ng]                        ~~~~~~~
[ng] src/app/home/home.page.ts:2:31 - error TS2305: Module '"../../../node_modules/@angular/common/http"' has no exported member 'RequestOptions'.
[ng] 2 import { HttpClient, Headers, RequestOptions } from '@angular/common/http';
[ng]                                 ~~~~~~~~~~~~~~
[ng] src/app/home/home.page.ts:28:11 - error TS2339: Property 'http' does not exist on type 'HomePage'.
[ng] 28      this.http.post("http://localhost/android/Api.php?apicall=signup", postData, requestOptions)
[ng]              ~~~~
[ng] 

Answer 1

您从错误的包中导入了它。另外，Headers 已重命名为 HttpHeaders。

尝试以下操作:

import { RequestOptions } from 'http';
import { HttpHeaders } from '@angular/common/http';

此外，您不一定需要 RequestOptions。您也可以像这样直接传递 HttpHeaders:

let headers: HttpHeaders = req.headers;

if (this.authService.checkAuth()) {
    const token = 'something';
    headers = headers.set('Authorization', `Bearer ${token}`);
}

const authReq = req.clone({ headers });

我还发现 this.http 不存在，因此您需要将其注入(inject)到 constructor() 中，如下所示:

constructor(private http: HttpClient) {}

根据您的情况，您可以像这样发送请求:

this.http.post("http://localhost/android/Api.php?apicall=signup", postData, { headers });

其中 { headers } 是您的 RequestOptions 对象，并且是 { headers: headers }

的简写

(如果键和值相同，则无需定义它们)

希望有帮助:)