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“rxjs”可见。投掷不是函数-角度4

throw observable rxjs angular

nick gowdy · 技术社区 · 7 年前

我一直在学习Angular 4,在我尝试在服务中实现捕捉处理之前,一切都进展顺利。我试图使用“rxjs”捕捉并抛出,但我的控制台中有一个未定义的函数错误。

import { Injectable } from '@angular/core';
import { Http } from "@angular/http";
import { Observable } from 'rxjs/observable';
import 'rxjs/add/operator/catch';
import 'rxjs/add/observable/throw';
import { AppError } from "../app/common/app.error";
import { NotFoundError } from "../app/common/not-found-error";
import { BadInput } from "../app/common/bad-input";

@Injectable()
export class PostService {
  private url = "https://jsonplaceholder.typicode.com/posts";

  constructor(private http: Http) { }

 deletepost(post){
      // return this.http.delete(this.url + '/' + post.id)
      // Hard-coded id to test 404
      return this.http.delete(this.url + '/' + 93498)
        .catch((error: Response) => {
          console.log('error within catch is ' + Response)
          if(error.status === 404)
            return Observable.throw(new NotFoundError(error));

          return Observable.throw(new AppError(error));
        });
    }
}

这是错误消息:

TypeError: __WEBPACK_IMPORTED_MODULE_2_rxjs_observable__["Observable"].throw is not a function. 
(In '__WEBPACK_IMPORTED_MODULE_2_rxjs_observable__["Observable"].throw(new 
__WEBPACK_IMPORTED_MODULE_6__app_common_not_found_error__["a" /* NotFoundError 
*/](error))', 
'__WEBPACK_IMPORTED_MODULE_2_rxjs_observable__["Observable"].throw' is 
undefined) â post.service.ts:42

./~/rxjs/Observable.js
There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* /Users/nickgowdy/Desktop/Angular2/angular4 source code/hello-world/node_modules/rxjs/Observable.js
    Used by 14 module(s), i. e.
    /Users/nickgowdy/Desktop/Angular2/angular4 source code/hello-world/node_modules/@angular/core/@angular/core.es5.js
* /Users/nickgowdy/Desktop/Angular2/angular4 source code/hello-world/node_modules/rxjs/observable.js
    Used by 1 module(s), i. e.
    /Users/nickgowdy/Desktop/Angular2/angular4 source code/hello-world/node_modules/@ngtools/webpack/src/index.js!/Users/nickgowdy/Desktop/Angular2/angular4 source code/hello-world/src/services/post.service.ts

5 回复 | 直到 5 年前

126

Dharman Fitopawer 4 年前

错误 There are multiple modules with names that only differ in casing. Observable .

导入应使用大写字母“O”,如:

import { Observable } from 'rxjs/Observable';

可观察的 catch throw 在创建的观察值上。

import 'rxjs/add/operator/catch';
import 'rxjs/add/observable/throw';

要导入完整的可观察对象,请按如下方式导入:

import { Observable } from 'rxjs/Rx'

map() 和 filter() 可以用作 pipeable operators pipe()

import { filter, map, catchError } from 'rxjs/operators';

投 操作员导入为:

import { _throw } from 'rxjs/observable/throw';

import { throwError } from 'rxjs';

然后抛出如下错误:

if (error.status === 404)
    return throwError( new NotFoundError(error) )

prijesh bhingradiya 5 年前

在RxJS 6中, Observable.throw() 替换为 throwError() 其运行方式与其前身非常相似。 Observable.throw(error) 仅适用于 throwError(error) 通过导入:

import { throwError } from 'rxjs';

https://www.metaltoad.com/blog/angular-6-upgrading-api-calls-rxjs-6

Sibeesh Venu 6 年前

我在工作中也面临着同样的问题 angular 5

import { throwError } from 'rxjs';
import { filter, map, catchError } from 'rxjs/operators';

从我的 http 服务调用我返回一个函数。

return this.http.request(request)
      .pipe(map((res: Response) => res.json()),
        catchError((res: Response) => this.onError(res)));

onError 返回错误的函数 throwError(error) .

onError(res: Response) {
    const statusCode = res.status;
    const body = res.json();
    const error = {
      statusCode: statusCode,
      error: body.error
    };
    return throwError(error);
  }

Waleed Shahzaib 5 年前

_在RxJS的较新版本中,throw已被丢弃
对于较新版本的RxJS(6+),请使用以下选项:

 import { throwError } from 'rxjs';

 if (error.status === 404)
    return throwError( new NotFoundError(error) )

Rob Lassche 4 年前

角度9可见:

如果数据到达且状态正常,则发送数据

myObsFunc(): Observable<any> { 
  return this.http.get<any>('/api/something') 
    .pipe(
      /* Catch a backend error and let the component know */
      catchError( err => {
        /* Rethrow error */
        return throwError( err );
      }),
      map( (res)=> {
        if( res.STATUS == "OK" ) {
          /* Send DATA to subscriber */
          return Object.values( res.DATA)
        } else {
           /* Inform subscriber that a functional error occured */
           throw ( "getOrphans: Status is not OK but "+ res.STATUS ) ;
        }   
      }),
    )   
}