当使用http.get - HttpClient - Angular断开连接时，可以替换URL

import { HttpClient } from '@angular/common/http';
import { catchError } from 'rxjs/operators';
import { throwError } from 'rxjs';

constructor(private http: HttpClient) {}

getData() {
  const url = 'http://example.com/api/data';

  this.http.get(url).pipe(
    catchError(error => {
      // 处理连接断开的错误
      // 可以在这里尝试替换URL
      return throwError(error);
    })
  ).subscribe(
    response => {
      // 处理请求成功的响应数据
    },
    error => {
      // 处理其他错误
    }
  );
}

import { HttpClient } from '@angular/common/http';
import { catchError } from 'rxjs/operators';
import { throwError } from 'rxjs';

constructor(private http: HttpClient) {}

getData() {
  const url = 'http://example.com/api/data';
  const backupUrl = 'http://backup.example.com/api/data';

  this.http.get(url).pipe(
    catchError(error => {
      // 处理连接断开的错误
      // 尝试替换URL为备用URL
      return this.http.get(backupUrl);
    })
  ).subscribe(
    response => {
      // 处理请求成功的响应数据
    },
    error => {
      // 处理其他错误
    }
  );
}