在Angular2中，需要文本框中的值的总和

<input type="text" [(ngModel)]="value1">
<input type="text" [(ngModel)]="value2">
<input type="text" [(ngModel)]="value3">

export class MyComponent {
  value1: number;
  value2: number;
  value3: number;

  calculateSum() {
    let sum = this.value1 + this.value2 + this.value3;
    return sum;
  }
}

<p>总和：{{ calculateSum() }}</p>