Question

<select class="example-full-width js-example-basic-single" #country name="country" [(ngModel)]="companycountryValue" required>
  <option *ngFor="let country of countrydata" [value]="country.name">{{ country.value }}</option>
</select>

如何将第一个选项选择为默认选项？ [（ngModel）] =“ companycountryValue”已经选择了数据，但也尝试了许多方法都无法使用。

Answer 1

只需在组件中做

this.companycountryValue="some default country.name value"

仅建议将默认值分配给country.name下隐藏的任何内容，因此将选择带有此[value]的选项

奖金：您不想这样做吗？

 <option *ngFor="let country of countrydata" [value]="country.value">{{ country.name}}</option>

Answer 2

有两种方法可以解决问题

Step1：//获取选项的索引并将其设置为html 像这样的属性：

    <select class="example-full-width js-example-basic-single" #country name="country" [(ngModel)]="companycountryValue" required>
  <option *ngFor="let country of countrydata; let i = index" [value]="country.name" [selected]="i == 0 ? true : null" >{{ country.value }}</option>
</select>

Step2：从组件设置到选择

ngOnit(){
          this.companycountryValue=countrydata[0];
}

并且在html中可以设置为

<select class="example-full-width js-example-basic-single" #country name="country" [(ngModel)]="companycountryValue" required>
  <option *ngFor="let country of countrydata" [value]="country.name">{{ country.value }}</option>
</select>

select2 angular2 +将第一个值设置为默认值

2 个答案: