how to get value from textbox using typescript in angular 2

if you get without using ngModel:

var   num1= ((document.getElementById("num1") as HTMLInputElement).value);
var   num2= ((document.getElementById("num2") as HTMLInputElement).value);
var result=parseInt(num1)+parseInt(num2);
console.log(result);

HTML

<p>first number:<input type="number" [(ngModel)]='a'></p>
<p>second number:<input type ="number" [(ngModel)]='b'></p>
<h1>{{a + b}}</h1>

Component

export class AppComponent 
  { 
 a: number = 0; //set default value as 0
 b: number = 0;

}

The easiest way is to use template reference variable:

@Component({
  selector: 'app-little-tour',
  template: `
    <input #newHero > 
    <button (click)="addHero(newHero.value)">Add</button>
})

export class LittleTourComponent {
  addHero(newHero: string) {
    console.log(newHero)
  }
}

A complete guide for User Input in Angular can be found here: https://angular.io/guide/user-input

HTML

<p>first number:<input type="text" id="num1" [(ngModel)] = "value" ></p>
<p>second number:<input type ="text1" id="num2" [(ngModel)] = "value1"></p>
<h1> {{value + value1}}</h1>

Component class

 export class AppComponent {}