问解角9中的HttpClient误差

EN

import { Injectable } from '@angular/core';
import {HttpClient} from '@angular/common/http';
import {observable, Observable}  from 'rxjs';
import {Signup} from './signup';
import { from } from 'rxjs';

@Injectable({
  providedIn: 'root'
})
export class SignupserviceService {
  createsignup(signup: Signup):Observable<Signup> {
    throw new Error("Method not implemented.");
    return this.http.post<Signup>(this.url+'api/users',signup)
    
  }
  url="http://localhost:51180/";

  constructor(private http:HttpClient) { }

  createuser(user:Signup):Observable<Signup>
  {
     return this.http.post<Signup>(this.url+'api/users',user)
  }
}

import { Component, OnInit } from '@angular/core';
import {FormBuilder,Validators,FormGroup} from '@angular/forms';
import {SignupserviceService} from '../signup/signupservice.service';
import {Signup} from '../signup/signup';
import { from } from 'rxjs';


@Component({
  selector: 'app-signup',
  templateUrl: './signup.component.html',
  styleUrls: ['./signup.component.css']
})
export class SignupComponent implements OnInit {
  navbarOpen = false;
  regForm: FormGroup;
  datasaved:boolean= false;
  massage: string;

  toggleNavbar() {
    this.navbarOpen = !this.navbarOpen;
  }

  constructor(private formbuilder: FormBuilder, private signupservice:SignupserviceService
    ) { }

  ngOnInit(): void {
  }




  setFormState(): void {
    this.regForm = this.formbuilder.group({
      email: ['', [Validators.required]],
      password: ['', [Validators.required]]
    })
  }

  onSubmit() {
    
    let signup = this.regForm.value;

    this.createsignup(signup);
    this.regForm.reset();
  }

  createsignup(signup: Signup) {
    this.signupservice.createsignup(signup).subscribe(
      () => {
        this.datasaved = true;
        this.massage = "User Created";
       this.regForm.reset();
      }
    )
  }

}

ERROR in node_modules/@angular/common/http/http.d.ts:81:22 - error NG6002: Appears in the NgModule.imports of AppModule, but could not be resolved to an NgModule class.

This likely means that the library (@angular/common/http) which declares HttpClient has not been processed correctly by ngcc, or is not compatible with Angular 
Ivy. Check if a newer version of the library is available, and update if so. Also consider checking with the library's authors to see if the library is expected to be compatible with Ivy.

81 export declare class HttpClient {

{
  "name": "localpost",
  "version": "0.0.0",
  "scripts": {
    "ng": "ng",
    "start": "ng serve",
    "build": "ng build",
    "test": "ng test",
    "lint": "ng lint",
    "e2e": "ng e2e"
  },
  "private": true,
  "dependencies": {
    "@angular/animations": "~10.0.6",
    "@angular/common": "~10.0.6",
    "@angular/compiler": "~10.0.6",
    "@angular/core": "~10.0.6",
    "@angular/forms": "~10.0.6",
    "@angular/platform-browser": "~10.0.6",
    "@angular/platform-browser-dynamic": "~10.0.6",
    "@angular/router": "~10.0.6",
    "@icon/icofont": "^1.0.1-alpha.1",
    "angular-font-awesome": "^3.1.2",
    "aos": "^2.3.4",
    "boxicons": "^2.0.5",
    "counterup2": "^1.0.4",
    "countup.js": "^2.0.6",
    "font-awesome": "^4.7.0",
    "ngx-bootstrap": "^5.6.1",
    "ngx-owl-carousel-o": "^4.0.0",
    "remixicon": "^2.5.0",
    "rxjs": "~6.5.5",
    "tslib": "^2.0.0",
    "waypoints": "^4.0.1",
    "zone.js": "~0.10.3"
  },
  "devDependencies": {
    "@angular-devkit/build-angular": "~0.1000.5",
    "@angular/cli": "~10.0.5",
    "@angular/compiler-cli": "~10.0.6",
    "@types/node": "^12.11.1",
    "@types/jasmine": "~3.5.0",
    "@types/jasminewd2": "~2.0.3",
    "codelyzer": "^6.0.0",
    "jasmine-core": "~3.5.0",
    "jasmine-spec-reporter": "~5.0.0",
    "karma": "~5.0.0",
    "karma-chrome-launcher": "~3.1.0",
    "karma-coverage-istanbul-reporter": "~3.0.2",
    "karma-jasmine": "~3.3.0",
    "karma-jasmine-html-reporter": "^1.5.0",
    "protractor": "~7.0.0",
    "ts-node": "~8.3.0",
    "tslint": "~6.1.0",
    "typescript": "~3.9.5"
  }
}

import { BrowserModule } from '@angular/platform-browser';
import { NgModule } from '@angular/core';

import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';

import { BodyComponent } from './component/body/body.component';
import { FooterComponent } from './component/footer/footer.component';
import { LoginComponent } from './component/login/login.component';
import { SignupComponent } from './component/signup/signup.component';
import { SignupserviceService } from './component/signup/signupservice.service';
import { HttpClientModule, HttpClient } from '@angular/common/http';



@NgModule({
  declarations: [
    AppComponent,
    BodyComponent,
    FooterComponent,
    LoginComponent,
    SignupComponent,
    
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    HttpClientModule,
    HttpClient
  ],
  providers: [SignupserviceService],
  bootstrap: [AppComponent]
})
export class AppModule { }