Javascript 如何在Angular8中创建通用请求服务
我创建了一个通用请求服务,但它一直返回“ZoneAwarePromise”。我尝试使用.pipe()和.subscribe()来尝试检索请求的内容,但它不起作用 requester.service.tsJavascript 如何在Angular8中创建通用请求服务,javascript,angular,typescript,promise,Javascript,Angular,Typescript,Promise,我创建了一个通用请求服务,但它一直返回“ZoneAwarePromise”。我尝试使用.pipe()和.subscribe()来尝试检索请求的内容,但它不起作用 requester.service.ts import { Injectable } from '@angular/core'; import { HttpClient } from '@angular/common/http'; @Injectable({ providedIn: 'root' }) export class R
import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
@Injectable({
providedIn: 'root'
})
export class RequesterService {
constructor(private http: HttpClient) { }
request(method, url, headers, body, params) {
return this.http.request(method, url, {
body: body || {},
headers: headers || {},
params: params || {}
})
}
async get(url, params?, headers?, data?) {
return await this.request('get', url, params, headers, data)
}
async post(url, params, headers, data) {
return await this.request('post', url, params, headers, data);
}
async put(url, params, headers, data) {
return await this.request('put', url, params, headers, data);
}
async delete(url, params, headers, data) {
return await this.request('delete', url, params, headers, data);
}
}
gym-list.component.ts
import { Component, OnInit } from '@angular/core';
import { RequesterService } from 'src/app/core/Requester/requester.service';
@Component({
selector: 'app-gym-list',
templateUrl: './gym-list.component.html',
styleUrls: ['./gym-list.component.css']
})
export class GymListComponent implements OnInit {
constructor(private Requester: RequesterService) { }
ngOnInit() {
console.log(this.teste())
}
async teste() {
await this.Requester.get('https://searchs.glitch.me/proposalcontent')
}
}
您正在尝试使用wait返回一个非异步函数
request(method, url, headers, body, params) {
return this.http.request(method, url, {
body: body || {},
headers: headers || {},
params: params || {}
})
}
async get(url, params?, headers?, data?) {
return await this.request('get', url, params, headers, data)
}
这里不应该使用异步等待系统
试试这个:
get(url, params?, headers?, data?) {
return this.request('get', url, params, headers, data)
}
并在component.ts文件中订阅此方法
像这样:
Requester.get.subscribe(....)
实际上,您可以创建一个可以在任何服务中扩展的抽象基本服务类。这将通过调用另一个具有通用错误处理代码的服务来自动处理错误。如果您传递了
customError
标志,则错误将返回到组件中以处理自定义错误。此方法使用的是RxJs
可观测值
,可在component.ts中订阅,并捕获响应和错误
import { HttpClient, HttpHeaders } from "@angular/common/http";
import { Observable } from "rxjs";
import { tap } from "rxjs/operators";
import { HttpOptionsService } from "../../services/httpoptions.service";
export abstract class ServiceBase {
constructor(
private http: HttpClient,
private httpOptionService: HttpOptionsService
) {}
httpOptions = {
headers: new HttpHeaders({
"Content-Type": "application/json"
})
};
getFormattedPostRequest(
url: string,
body: any,
customError: boolean = false): Observable<any> {
return this.pipeTapObservable(
this.http.post(url, body, this.httpOptions),
customError
);
}
getFormattedPutRequest(
url: string,
body: any,
customError: boolean = false
): Observable<any> {
return this.pipeTapObservable(
this.http.put(url, body, this.httpOptions),
customError
);
}
getFormattedGetRequest(
url: string,
customError: boolean = false
): Observable<any> {
return this.pipeTapObservable(
this.http.get(url, this.httpOptions),
customError
);
}
getFormattedDeleteRequest(
url: string,
customError: boolean = false
): Observable<any> {
return this.pipeTapObservable(
this.http.delete(url, this.httpOptions),
customError
);
}
private pipeTapObservable(
request: Observable<any>,
customError: boolean = false
): Observable<any> {
return request.pipe(
tap(
response => response,
error => {
!customError &&
this.httpOptionService.handleError(error);
return error;
}
)
);
}
}
您可以使用async/await,但是这种语法用于promise类型,而request方法返回一个可观察的对象,因此您只需要从request方法返回一个promise,或者您可以在get、post、put、delete方法的return语句中执行
从'@angular/core'导入{Injectable};
从'@angular/common/http'导入{HttpClient};
@注射的({
providedIn:'根'
})
导出类请求服务{
构造函数(私有http:HttpClient){}
请求(方法、url、标题、正文、参数){
返回此.http.request(方法、url、{
body:body |{},
标题:标题| |{},
params:params | |{}
}).toPromise();
}
获取(url、参数、标题、数据){
返回此.request('get',url,params,headers,data);
}
post(url、参数、标题、数据){
返回此.request('post',url,params,headers,data);
}
put(url、参数、标题、数据){
返回此.request('put',url,params,headers,data);
}
删除(url、参数、标题、数据){
返回此.request('delete',url,params,headers,data);
}
}
组成部分
从'@angular/core'导入{Component,OnInit};
从'src/app/core/Requester/Requester.service'导入{RequesterService};
@组成部分({
选择器:“应用程序健身房列表”,
templateUrl:'./gym list.component.html',
样式URL:['./gym list.component.css']
})
导出类GymListComponent实现OnInit{
构造函数(私有请求者:请求者服务){}
恩戈尼尼特(){
console.log(this.teste())
}
异步测试(){
const result=wait this.Requester.get('https://searchs.glitch.me/proposalcontent');
console.log(result);从“@angular/common/http”导入{HttpClient,HttpHeaders,HttpRequest,HttpEventType,HttpEvent,HttpResponse,HttpErrorResponse};
从'rxjs'导入{observatable,from};
从“/igeneric http客户端”导入{IGenericHttpClient};
从“@angular/core”导入{Injectable};
从“../view models/component type.enum”导入{HttpMethod}
从“../view models/interface”导入{IRequestOptions};
从“../view models/environment view model”导入{environment ViewModel};
从“rxjs/operators”导入{retry};
@可注射()
导出类GenericHttpClient实现IGenericHttpClient{
构造函数(私有httpClient:httpClient,私有环境:EnvironmentViewModel){}
public Post(destinationUrl:string,options?:iRequestStoptions):可观察{
返回此.request(HttpMethod.Post、destinationUrl、options);
}
公共看跌期权(destinationUrl:string,options?:IRequestOptions):可观察{
返回此.request(HttpMethod.Put、destinationUrl、options);
}
public Get(destinationUrl:string,options?:IRequestOptions):可观察{
返回此.request(HttpMethod.Get、destinationUrl、options);
}
公共删除(destinationUrl:string,options?:iRequestStoptions):可观察{
返回此.request(HttpMethod.Delete、destinationUrl、options);
}
私有请求(方法:string,url:string,选项?:IRequestOptions):可观察{
返回可观察的。创建((观察者:任意)=>{
this.httpClient.request(新的HttpRequest(方法,this.environment.baseUrl+url,选项)).subscribe(
(答复:任何)=>{
const responsTye=响应为HttpEvent
开关(响应类型){
案例HttpEventType。已发送:
log('Request sent!');
打破
案例HttpEventType.ResponseHeader:
log('Response header received!');
打破
案例HttpEventType.DownloadProgress:
常量kbLoaded=Math.round(responsTye.loaded/1024);
log(`Download in progress!${kbLoaded}kbLoaded`);
打破
案例HttpEventType。响应:
观察者。下一步(响应。正文);
console.log('您是否在RequesterService
中尝试了不使用async
和wait
的逻辑?我从来没有使用过带有可观察对象的逻辑,因此这将是我的第一个想法,即尝试使用管道和订阅的原因。Requester.get(url,…)如何
比http.get(url,…)
更简单吗?使用async/Wait没有错,您必须将observable转换为promise,observable对此有一个方法,如果有效,请检查m答案
@Injectable()
export class MyService extends ServiceBase {
constructor(
http: HttpClient,
httpOptionService: HttpOptionsService
) {
super(http, httpOptionService);
}
}