angular - 如何在下拉列表中显示来自数据源的第一项

Question

我试图在我的下拉列表中显示数据源中的第一个。

我正在使用下一个代码：

html

<form [formGroup]="filtersForm" class="filters-row">
 <div class="flex-column">
  <select label="Number." [options]="aNumberDropdown" formControlName="dropdownNumber"></select>
  </div>
</form>

组件.ts

  public filtersForm = this.formBuilder.group({
      dropdownNumber: ['']
  });

标签： angularangular8

Answer 1

html

  <form [formGroup]="filtersForm" class="filters-row">
    <div class="flex-column">
      <select label="Number." formControlName="dropdownNumber">
        <option *ngFor="let aNumber of aNumberDropdown" [ngValue]="aNumber">{{aNumber}}</option>
      </select>
    </div>
  </form>

组件.ts

  public filtersForm: FormGroup = this.formBuilder.group({
    dropdownNumber: [this.aNumberDropdown[0]]
  });