Angular实现动态添加删除表单输入框功能

 <div class="form-group form-group-sm" *ngFor="let i of login">
     <label class="col-form-label">用户名</label>
     <input class="form-control" [(ngModel)]="i.username" value="{{i.username}}">
     <label class="col-form-label">密码</label>
     <input class="form-control" [(ngModel)]="i.password" value="{{i.password}}">
     <button class="btn btn-link" (click)="removeInput(i)">删除</button>
   </div>
   <button (click)="addInput()">增加</button>

 private id: string;
   login: any = [{ 'username': 'username' + this.id, 'password': 'pwd' + this.id }];

   addInput() {
     console.log('点击');
     console.log(this.login);
     const number = this.login.length + 1;
     this.login.push({ 'username': 'username' + number, 'password': 'pwd' + number });
     console.log(this.login);
   }

   removeInput(item) {
     console.log(item);
     const i = this.login.indexOf(item);
     console.log(i);
     this.login.splice(i, 1);
   }