下面是一个使用Angular和Google Calendar API的代码示例：

1. 首先，安装必要的依赖：

npm install --save @types/gapi
npm install --save @types/gapi.auth2
npm install --save @types/gapi.client.calendar

2. 创建一个GoogleAuthService服务，用于处理Google身份验证： google-auth.service.ts

import { Injectable } from '@angular/core';

@Injectable()
export class GoogleAuthService {
  private authInstance: gapi.auth2.GoogleAuth;

  public loadAuth2(): Promise {
    return new Promise((resolve, reject) => {
      gapi.load('auth2', () => {
        gapi.auth2.init({
          client_id: 'YOUR_CLIENT_ID'
        }).then((authInstance: gapi.auth2.GoogleAuth) => {
          this.authInstance = authInstance;
          resolve();
        }, (error) => {
          reject(error);
        });
      });
    });
  }

  public signIn(): Promise {
    return this.authInstance.signIn();
  }

  public signOut(): Promise {
    return this.authInstance.signOut();
  }

  public isSignedIn(): boolean {
    return this.authInstance.isSignedIn.get();
  }

  public getCurrentUser(): gapi.auth2.GoogleUser {
    return this.authInstance.currentUser.get();
  }
}

3. 创建一个GoogleCalendarService服务，用于与Google Calendar API进行通信： google-calendar.service.ts

import { Injectable } from '@angular/core';
import { GoogleAuthService } from './google-auth.service';

@Injectable()
export class GoogleCalendarService {
  private calendarApiLoaded: Promise;

  constructor(private authService: GoogleAuthService) {
    this.calendarApiLoaded = new Promise((resolve, reject) => {
      gapi.load('client', () => {
        gapi.client.load('calendar', 'v3', () => {
          resolve();
        });
      });
    });
  }

  public getEvents(): Promise {
    return this.calendarApiLoaded
      .then(() => {
        return gapi.client.calendar.events.list({
          calendarId: 'primary',
          timeMin: (new Date()).toISOString(),
          showDeleted: false,
          singleEvents: true,
          orderBy: 'startTime'
        });
      })
      .then((response) => {
        return response.result;
      });
  }
}

4. 在你的Angular组件中使用GoogleAuthService和GoogleCalendarService： app.component.ts

import { Component, OnInit } from '@angular/core';
import { GoogleAuthService } from './google-auth.service';
import { GoogleCalendarService } from './google-calendar.service';

@Component({
  selector: 'app-root',
  template: `
    Sign In
    Sign Out
    

      
Upcoming Events:
      

        
{{ event.summary }}
      
    
    

      
Please sign in to view events
    
  `
})
export class AppComponent implements OnInit {
  public isSignedIn: boolean;
  public events: gapi.client.calendar.Event[];

  constructor(private authService: GoogleAuthService, private calendarService: GoogleCalendarService) {}

  public ngOnInit() {
    this.isSignedIn = this.authService.isSignedIn();
    if (this.isSignedIn) {
      this.loadEvents();
    }
  }

  public signIn() {
    this.authService.signIn()
      .then(() => {
        this.isSignedIn = true;
        this.loadEvents();
      });
  }

  public signOut() {
    this.authService.signOut()
      .then(() => {
        this.isSignedIn = false;
        this.events = [];
      });
  }

  private loadEvents() {
    this.calendarService.getEvents()
      .then((events) => {
        this.events = events.items;
      });
  }
}

以上代码演示了如何使用Angular和Google Calendar API进行身份验证并获取用户的日历事件。请确保替换YOUR_CLIENT_ID为您的Google API客户端ID。