Create a directive to check no special characters allowed: import {Directive, forwardRef} from '@angular/core'; import {AbstractControl, NG_VALIDATORS, Validator} from'@angular/forms'; @Directive({ selector: `[formControl][no-special-chars], [formControlName][no-special-chars], [ngModel][no...
首先为 form 标签添加 formGroup 指令: 并且为 input 标签添加 formControlName 指令: 复制代码 代码如下: 3、在代码中定义验证规则: 从内置表单模块中导入以下类: import { FormBuilder, FormGroup, Validators } from '@angular/forms'; 其中: 1. formBuilder 用来构建表单数据 2. formGroup 表示表单类型 3....
打开app.component.ts并用以下代码替换内容: import { Component, OnInit } from '@angular/core';import { FormBuilder, FormGroup, Validators } from '@angular/forms';import { ValidateUrl } from '../shared/url.validator';@Component({selector: 'app-root',templateUrl: './app.component.html',sty...
validators: CustomFormValidators.passwordsMustMatch( 'password', 'passwordconf' ), } 创建FormGroup时,第二个参数是配置对象,用于配置表单级别的验证器,这里有一个自定义的验证器CustomFormValidators.passwordsMustMatch,它确保password和passwordconf两个控件的值必须匹配。 自定义验证器passwordsMustMatch 通过代码可...
: DateTimePickerComponent; public formObject?: FormValidator; ngOnInit() { // custom validator function. let customFn: (args: { [key: string]: string }) => boolean = (args: { [key: string]: string }) => { return (((this.ejDateTime as DateTimePickerComponent ).value).getFull...
HTML forms. Form validators not only help you to get better quality data but they also guide the user through your form. Angular comes with a series of built-in validators such asrequiredormaxLengthetc. But very soon you have to build your own custom validators to handle more complex ...
// custom validator forbiddenText = 'test'; email = 'test@test.com'; emailFormControl = new FormControl('test@test.com', [Validators.forbidden(this.forbiddenText)]); } 完整代码可参见stackblitz demo。 所以,在理解了 Validator 内部运行原理后,不仅仅可以写自定义的 Validator,该 Validator 可以用于...
Define a custom validator: import {FormControl}from"@angular/forms"; export function validateDuration(ctrl:FormControl){constnumValue =parseInt(ctrl.value);constvalid = numValue <10;returnvalid ?null: { validateDuration: { valid:false,
selector: `[formControl][no-special-chars], [formControlName][no-special-chars], [ngModel][no-special-chars]`, providers: [ { multi:true, provide: NG_VALIDATORS, useExisting: forwardRef(()=>NoSpecialCharsValidator) } ] }) export class NoSpecialCharsValidator implements Validator { ...
this.fb.array([]), }, { validators: CustomFormValidators.passwordsMustMatch( 'password', 'passwordconf' ), } ); 这个注册表单具体是由 FormBuilder 实例fb 创建的。FormBuilder 是Angular 提供的一个帮助类,它旨在简化表单的创建。 使用fb.group 创建表单组: this.fb.group 方法用来创建一个 FormGroup...