angular2 表单验证 : get an instance of ngForm

Question

如何在组件中引用“myform”？是否可以？一定要使用 formbuilder(我尽量避免使用它)吗？

<form #myForm="ngForm">
    <label class="col-sm-12" [class.ng-invalid]="!(value.valid || Value.pristine)">Value</label>
    <input type="text"  required ngControl="value" #value="ngForm" class="form-control text-center" [(ngModel)]="value" />
  </form>

Answer 1

实际上还有另一种方法可以做到这一点。您可以使用 ViewChild 注释，此处您的示例已改编:

<form #myForm="ngForm">
<label class="col-sm-12" [class.ng-invalid]="!(value.valid || Value.pristine)">Value</label>
<input type="text"  required ngControl="value" #value="ngForm" class="form-control text-center" [(ngModel)]="value" />

class MyForm {
  @ViewChild('myForm') form;
  ngAfterViewInit() {
    console.log(this.form)
    this.form.control.valueChanges
      .subscribe(values => console.log(values));
  }
}