Angular 5.2 自定义 HttpClient class - 无法将响应类型更改为 blob

Question

我在我的项目中使用 Angular 5.2 版本并且运行将默认 responseType 更改为具有新功能的 blob 存在问题。

现在我想将 responseType 更改为 blob 以下载 excel 文件，但它对我不起作用。

在我的项目中，我创建了包装器 class 作为 CustomHttpClient 来进行 Get 或 Post 调用。

CustomHttpClient class 看起来像这样：-

    export interface IRequestOptions {

    headers?: HttpHeaders;
    observe?: 'body';
    params?: HttpParams;
    reportProgress?: boolean;
    responseType?: 'json';
    withCredentials?: boolean;
    body?: any;
}


/*Custom HttpClient Class for making the WebAPI calls.*/
export class CustomHttpClient {

    _defaultHeaderType = new HttpHeaders({ 'Content-Type': 'application/json' });

    // Extending the HttpClient through the Angular DI.
    public constructor(public _http: HttpClient) {

    }

  public Get<T>(endPoint: string, options?: IRequestOptions): Observable<T> {
        if (options == undefined) {
            options = <IRequestOptions>{};
            options.headers = this._defaultHeaderType
        }

        options.headers = this.injectClient(options.headers);
        return this._http.get<T>(endPoint, options);
    }

    public GetBlob<T>(endPoint: string, options?: IRequestOptions): Observable<T> {
        if (options == undefined) {
            options = <IRequestOptions>{};
            options.headers = this._defaultHeaderType
        }

        //This line is giving error
         options.responseType = 'blob';

        options.headers = this.injectClient(options.headers);
        return this._http.get<T>(endPoint, options);
    }
}

现在我想调用 GetBlob 函数并将 responseType 更改为 'blob'。但它向我显示错误 "Type "blob" is not assignable to type "Json"".

从组件服务 class，我这样调用 fn :-

downloadTemplate(): Observable<any> {
    let opt = {
        headers: new HttpHeaders({ 'Content-Type': 'application/json', 'Accept': 'application/xlsx'}),
        options: new RequestOptions({ responseType: ResponseContentType.Blob })
    }

    return this._httpObj.GetBlob(this._baseUrl + 'DownloadTemplate', opt);
}

Answer 1

尝试更改您的 RequestOptions 接口，使响应类型为字符串类型。像这样：

  export interface IRequestOptions {

    headers?: HttpHeaders;
    observe?: 'body';
    params?: HttpParams;
    reportProgress?: boolean;
    responseType?: string;
    withCredentials?: boolean;
    body?: any;
}

Answer 2

最近遇到了同样的问题，希望他们能尽快解决。我使用 Object.assign 作为解决方法：

this._http.get<T>(endPoint, Object.assign(options, { responseType: 'blob' }))

这样你就可以在 ts 类型检查上作弊。

Angular 5.2 自定义 HttpClient class - 无法将响应类型更改为 blob

Angular 5.2 Custom HttpClient class - Unable to change the responseType to blob

angular

angular-httpclient

angular5