hello.view.html

<div style="background: ghostwhite">
    <h3>
        <label>Name:</label>

        <!--binding to component field-->
        <input type="text" [(ngModel)]="name" placeholder="Enter a name here">

        <!--binding click event to component method-->
        <button class="btn btn-primary col-md-2" (click)="sayHello()">
            Hello!
        </button>
    </h3>

    <!-- conditionally display `message` -->
    <h4 [hidden]="!message">{{message}}</h4>
</div>