[英]Angular 5 validation error not shown on input change
我對輸入控件有問題,如果我輸入501(無效值),則除非輸入失去焦點,否則不會顯示mat-error。 當用戶輸入無效值而沒有輸入失去焦點時,如何顯示它? 這是HTML
<div class="col-auto form margin-top-17 margin-left-10" [formGroup]="activationPointsFormGroup">
<mat-form-field style="width:230px!important">
<input matInput type="number" placeholder="Range" [formControl]="activationPointsFormControl"
(keydown.enter)="loadData()">
<mat-error class="margin-top-1" *ngIf="activationPointsFormControl.errors">
Valid values are between -500 and 500 and not 0
</mat-error>
</mat-form-field>
</div>
和打字稿代碼
public activationPointsFormGroup: FormGroup;
public activationPointsFormControl: FormControl;
private createForm(): void {
this.activationPointsFormControl = new FormControl(1, [Validators.required, Validators.min(-500), Validators.max(500)]);
this.activationPointsFormGroup = new FormGroup({
timeThresholdFormControl: this.activationPointsFormControl,
});
this.activationPointsFormControl.valueChanges.subscribe(value => {
if (value) {
this.selectedActivationPoints = value;
}
});
}
為此,您需要一個錯誤狀態匹配器 ,以自定義角度材料的驗證行為,導入ErrorStateMatcher
並...
import {ErrorStateMatcher} from '@angular/material/core';
export class MyErrorStateMatcher implements ErrorStateMatcher {
isErrorState(control: FormControl | null, form: FormGroupDirective | NgForm | null): boolean {
return !!(control && control.invalid && control.dirty);
}
}
現在,當控件dirty
時,將顯示錯誤消息。 在您的組件中聲明一個錯誤狀態匹配器...
matcher = new MyErrorStateMatcher();
然后將其標記在您的輸入字段上:
<input matInput [errorStateMatcher]="matcher" ...>
這是一個演示,它將顯示用戶輸入時電子郵件無效...
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.