Angular 2 RC6 表单控件验证消息

Angular 2 RC6 Forms control validation message

<form [formGroup]="registerForm" (submit)="onSubmit()">
    <label>Firstname:</label>
    <input type="text" formControlName="firstname">
    <p *ngIf="registerForm.controls.firstname.errors">This field is required!</p>
...

有没有办法让registerForm.controls.firstname.errors短一点?

一种方法是在表单组件中将较短的名称定义为 AbstractControl 属性。在各自的组件 Class 中,添加:

firstname: AbstractControl;

在构造函数中:

this.firstname = this.registerForm.controls['firstname'];

现在,您可以像这样访问字段属性:

<p *ngIf="firstname.errors">This field is required!</p>

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