在Angular中，如果授权头部为空，可能是因为在请求中未正确设置授权头部。

以下是一个解决方案的示例代码：

1. 创建一个AuthService服务，用于处理授权逻辑。

import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';

@Injectable({
  providedIn: 'root'
})
export class AuthService {
  private apiUrl = 'http://your-api-url';

  constructor(private http: HttpClient) { }

  login(username: string, password: string) {
    return this.http.post(`${this.apiUrl}/login`, { username, password });
  }

  getAuthenticatedData() {
    const token = localStorage.getItem('token');
    const headers = new HttpHeaders().set('Authorization', `Bearer ${token}`);
    return this.http.get(`${this.apiUrl}/data`, { headers });
  }
}

2. 在登录组件中调用AuthService的login方法来获取授权令牌。

import { Component } from '@angular/core';
import { AuthService } from 'path-to-auth-service';

@Component({
  selector: 'app-login',
  template: `
    

      
      
      Login
    
  `,
  styleUrls: ['./login.component.css']
})
export class LoginComponent {
  username: string;
  password: string;

  constructor(private authService: AuthService) { }

  login() {
    this.authService.login(this.username, this.password).subscribe(
      data => {
        localStorage.setItem('token', data.token);
        // Redirect to authenticated page
      },
      error => {
        console.error(error);
      }
    );
  }
}

3. 在需要进行授权的组件中，调用AuthService的getAuthenticatedData方法来获取授权数据。

import { Component, OnInit } from '@angular/core';
import { AuthService } from 'path-to-auth-service';

@Component({
  selector: 'app-data',
  template: `
    
{{ data }}
  `,
  styleUrls: ['./data.component.css']
})
export class DataComponent implements OnInit {
  data: any;

  constructor(private authService: AuthService) { }

  ngOnInit() {
    this.authService.getAuthenticatedData().subscribe(
      data => {
        this.data = data;
      },
      error => {
        console.error(error);
      }
    );
  }
}

通过以上代码示例，可以在Angular中正确设置授权头部，解决授权头部为空的问题。请注意，代码示例中的路径和URL需要根据实际情况进行修改。