Angular中选择框的默认“占位符”？

Question

I'm developing a web application (front-end size) using Angular 6. I have a question: I'm creating a component that contains different select-box, like this:

How can I create a reset() method that changes all the select-box with the placeholder value (without canceling or modifying the options associated with him in any way)? Is there any way that allows this by modifying the html template programmatically? Thanks!

Answer 1

you can use ngModel

 <select class="custom-select" [(ngModel)]="model.select"  name="select" id="combo">
      <option value=""></option>
      <option *ngFor="let item of list" [ngValue]="item">{{ item}}</option>
 </select>

component:

reset(){
   model.selct='';
}