1. 首先在组件中引入文件上传相关的服务和模块，如：

import { Component, OnInit } from '@angular/core';
import { FormBuilder, FormGroup, FormArray, Validators } from '@angular/forms';
import { HttpClient } from '@angular/common/http';
import { map } from 'rxjs/operators';
import { FileUploadService } from '../services/file-upload.service';

2. 创建表单数组，其中需要在每个表单项中包含文件上传的相关信息，如文件对象、文件名等等。示例代码如下：

this.formArray = this.formBuilder.array([
      this.formBuilder.group({
        name: ['', Validators.required],
        file: [null, Validators.required],
        fileName: ['']
      })
    ]);

3. 在模板中渲染表单，并添加文件上传组件，如下：

  

    

      
      
      Upload
      {{ item.value.fileName }}
    
  
  Submit

4. 在组件中实现文件上传的逻辑，根据文件上传成功后返回的URL等信息，更新表单中相应的文件名等信息。示例代码如下：

onFileChange(files: FileList, i: number) {
    const reader = new FileReader();
    if (files && files.length) {
      const [file] = files;
      reader.readAsDataURL(file);

      reader.onload = () => {
        this.formArray.controls[i].get('file').setValue(file);
        this.formArray.controls[i].get('fileName').setValue(file.name);
      };
    }
  }

  uploadFile(i: number) {
    const file = this.formArray.controls[i].get('file').value;

    this.fileUploadService.upload(file).pipe(
      map((event) => {
        if (event.type === HttpEventType.Response) {
          return event.body;
        } else if (event.type === HttpEventType.UploadProgress) {
          const percentDone = Math.round((100 * event.loaded) / event.total);
          console.log(percentDone);
        }
      })
    ).subscribe((response) => {
      console.log(response);
      this.formArray.controls[i].