javascript - 更新到 angular 8 后找不到模块@angular/common/http/src/params

Question

从 Angular 7 更新到最新版本 (8) 后，遇到了一些我能够解决的问题，但我找不到解决方案。

Cannot find module '@angular/common/http/src/params'.

我的代码:

        const options: HttpParamsOptions = {
            fromObject: params,
            encoder: this.httpParamEncoder
        };

Answer 1

可能你正在从 @angular/common/http/src/params 导入 HttpParamsOptions 接口(interface):

import { HttpParamsOptions } from '@angular/common/http/src/params';

这个问题在 Angular 的 Github 存储库上也有讨论: https://github.com/angular/angular/issues/23523 , https://github.com/angular/angular/issues/22013 , https://github.com/angular/angular/issues/20276

问题是 HttpParamsOptions 接口(interface)不是由公共(public) API 导出的，尽管它在作为公共(public) API 一部分的 HttpParams 中使用:

export declare class HttpParams {
    constructor(options?: HttpParamsOptions);
    ...
}

当前的解决方法是通过从 Angular 源代码中复制接口(interface)，将接口(interface)包含在您自己的代码中，如 https://github.com/angular/angular/blob/8a0e45826a4f140e9330d57594c338276a151401/packages/common/http/src/params.ts#L76 中所示。

/** Options used to construct an `HttpParams` instance. */
export interface HttpParamsOptions {
   /**
    * String representation of the HTTP params in URL-query-string format. Mutually exclusive with
    * `fromObject`.
    */
   fromString?: string;

   /** Object map of the HTTP params. Mutually exclusive with `fromString`. */
   fromObject?: {
      [param: string]: string | string[];
   };

   /** Encoding codec used to parse and serialize the params. */
   encoder?: HttpParameterCodec;
}

然后初始化http参数如下:

const httpParamsOptions: HttpParamsOptions = { fromObject: { aaa: '111', bbb: '222' } };
const httpParams = new HttpParams(httpParamsOptions);

具有完整代码的 StackBlitz 演示:https://stackblitz.com/edit/angular-cizc36 .