Angular 2属性和* ngIf

Question

什么是不正确的？如果错误如何使其正确，我想显示此属性？

<label for="email" *ngIf="(form.controls.email.errors && form.controls.email.dirty) ? true : [attr.data-error]="wrong" ">E-Mail</label>
<input type="email" name="email" autocomplete="off" formControlName="email">

Answer 1

<label for="email" [attr.data-error]="(form.controls.email.errors && form.controls.email.dirty)? 'wrong': null">E-Mail</label>

Answer 2

您可以尝试这样的事情

<label for="email"
 *ngIf="form.controls.email.errors && form.controls.email.dirty"
 [attr.data-error]="form.controls.email.errors && form.controls.email.dirty? 
 'wrong': ''" >
E-Mail</label>