Angular5+ 自定义表单验证器
Custom Validators
标签（空格分隔）： Angular
首先阐述一下遇到的问题：
- 怎样实现“再次输入密码”的验证（两个controller值相等）（equalTo）
- 怎样反向监听（先输入“再次输入密码”，后输入设置密码）
解决思路：
- 第一个问题，可以通过
[AbstractControl].root.get([targetName])来取得指定的controller，然后比较他们的值。 - 第二个，可以通过
[target].setErrors([errors])来实现。
- 这是一个我的自定义表单验证：
import {AbstractControl, FormGroup, ValidatorFn} from '@angular/forms';
import {G} from '../services/data-store.service';
export class MyValidators {
private static isEmptyInputValue(value) {
// we don't check for string here so it also works with arrays
return value == null || value.length === 0;
}
private static isEmptyObject(obj) {
if (typeof obj === 'object' && typeof obj.length !== 'number') {
return Object.keys(obj).length === 0;
}
return null;
}
/**
* 等于指定controller的值
* @param targetName 目标的formControlName
* @returns {(ctrl: FormControl) => {equalTo: {valid: boolean}}}
*/
static equalTo(targetName: string): ValidatorFn {
return (control: AbstractControl): {[key: string]: any} | null => {
const target = control.root.get(targetName);
if (target === null) {
return null;
}
if (this.isEmptyInputValue(control.value)) {
return null;
}
return target.value === control.value ? null : {'equalto': { valid: false }};
};
}
/**
* 反向输入监听指定controller是否与当前值相等
* @param targetName
*/
static equalFor(targetName: string): ValidatorFn {
return (control: AbstractControl): {[key: string]: any} | null => {
const target = control.root.get(targetName);
if (target === null) {
return null;
}
if (this.isEmptyInputValue(control.value)) {
return null;
}
if (target.value === control.value) {
const errors = target.errors;
delete errors['equalto'];
if (this.isEmptyObject(errors)) {
target.setErrors(null);
} else {
target.setErrors(errors);
}
return null;
}
target.setErrors({ 'equalto': { valid: false } });
};
}
...
}
(注:)其中G.REGEX等的是全局变量。
- 然后
FormBuilder来实现：
import { Component, OnInit } from '@angular/core';
import {EventsService} from '../../../services/events.service';
import {FormBuilder, FormGroup, Validators} from '@angular/forms';
import {G} from '../../../services/data-store.service';
import {fade} from '../../../animations/fade.animation';
import {MyValidators} from '../../../directives/my-validators.directive';
@Component({
selector: 'app-sign-up',
templateUrl: './sign-up.component.html',
styleUrls: ['./sign-up.component.scss'],
animations: [fade]
})
export class SignUpComponent implements OnInit {
signForm: FormGroup; // 表单组FormGroup
submitting: boolean; // 是否可以提交
validations = G.VALIDATIONS;
constructor(private eventsService: EventsService, private formBuilder: FormBuilder) {
this.submitting = false;
//
this.init();
}
ngOnInit() {
// 设置父组件标题
this.eventsService.publish('setSign', { title: '注册', subTitle: { name: '立即登录', uri: '/account/sign-in' } });
}
// 立即注册
onSubmit() {
console.log(this.signForm.getRawValue());
}
// 表单初始化
private init() {
this.signForm = this.formBuilder.group({
username: ['', Validators.compose([Validators.required, Validators.maxLength(this.validations.USR_MAX)])],
password: ['', Validators.compose([
Validators.required,
Validators.minLength(this.validations.PASS_MIN),
Validators.maxLength(this.validations.PASS_MAX),
MyValidators.equalFor('passwordConfirm')
])],
passwordConfirm: ['', Validators.compose([
Validators.required,
Validators.minLength(this.validations.PASS_MIN),
Validators.maxLength(this.validations.PASS_MAX),
MyValidators.equalTo('password')
])]
});
}
}
(注:)其中fade动画效果。
- 然后在html模板中，显示表单验证提示信息：
<form [formGroup]="signForm" (ngSubmit)="onSubmit()" class="sign-form" @fade>
<!-- 账号 -->
<div class="input-group username">
<span class="addon prev"><i class="civ civ-i-usr"></i></span>
<input type="text"
name="username"
class="form-control form-control-left default"
placeholder="请输入账号"
formControlName="username"
autocomplete="off">
<ul class="errors" *ngIf="signForm.get('username').invalid && (signForm.get('username').dirty || signForm.get('username').touched)">
<li *ngIf="signForm.get('username').hasError('required')" class="error">
请输入您的账号!
</li>
<li *ngIf="signForm.get('username').hasError('maxlength')" class="error">
账号不超过{{ validations.USR_MAX }}位!
</li>
</ul>
</div> <!-- /.账号 -->
<!-- 密码 -->
<div class="input-group password">
<span class="addon prev"><i class="civ civ-i-lock"></i></span>
<input type="password"
name="password"
class="form-control form-control-left default"
placeholder="请输入密码"
formControlName="password">
<ul class="errors" *ngIf="signForm.get('password').invalid && (signForm.get('password').dirty || signForm.get('password').touched)">
<li *ngIf="signForm.get('password').hasError('required')" class="error">
请输入您的密码!
</li>
<li *ngIf="signForm.get('password').hasError('minlength')" class="error">
请输入至少{{ validations.PASS_MIN }}位数的密码!
</li>
<li *ngIf="signForm.get('password').hasError('maxlength')" class="error">
密码不超过{{ validations.PASS_MAX }}位!
</li>
</ul>
</div> <!-- /.密码 -->
<!-- 重复密码 -->
<div class="input-group password-confirm">
<span class="addon prev"><i class="civ civ-i-lock"></i></span>
<input type="password"
name="passwordConfirm"
class="form-control form-control-left default"
placeholder="请再次输入密码"
formControlName="passwordConfirm">
<ul class="errors" *ngIf="signForm.get('passwordConfirm').invalid && (signForm.get('passwordConfirm').dirty || signForm.get('passwordConfirm').touched)">
<li *ngIf="signForm.get('passwordConfirm').hasError('required')" class="error">
请再次输入密码!
</li>
<li *ngIf="signForm.get('passwordConfirm').hasError('minlength')" class="error">
请输入至少{{ validations.PASS_MIN }}位数的密码!
</li>
<li *ngIf="signForm.get('passwordConfirm').hasError('maxlength')" class="error">
密码不超过{{ validations.PASS_MAX }}位!
</li>
<li *ngIf="!signForm.get('passwordConfirm').hasError('maxlength') && !signForm.get('passwordConfirm').hasError('minlength') && signForm.get('passwordConfirm').hasError('equalto')" class="error">
两次密码输入不一致!
</li>
</ul>
</div> <!-- /.重复密码 -->
<!-- 提交按钮 -->
<button type="submit"
class="btn btn-primary btn-block submit"
[disabled]="submitting || signForm.invalid">立即注册</button>
<!-- /.提交按钮 -->
</form>
最后，我们可以看到，实现了想要的效果：
(附:)完整的自定义表单验证器：
import {AbstractControl, FormGroup, ValidatorFn} from '@angular/forms';
import {G} from '../services/data-store.service';
export class MyValidators {
private static isEmptyInputValue(value) {
// we don't check for string here so it also works with arrays
return value == null || value.length === 0;
}
private static isEmptyObject(obj) {
if (typeof obj === 'object' && typeof obj.length !== 'number') {
return Object.keys(obj).length === 0;
}
return null;
}
/**
* 等于指定controller的值
* @param targetName 目标的formControlName
* @returns {(ctrl: FormControl) => {equalTo: {valid: boolean}}}
*/
static equalTo(targetName: string): ValidatorFn {
return (control: AbstractControl): {[key: string]: any} | null => {
const target = control.root.get(targetName);
if (target === null) {
return null;
}
if (this.isEmptyInputValue(control.value)) {
return null;
}
return target.value === control.value ? null : {'equalto': { valid: false }};
};
}
/**
* 反向输入监听指定controller是否与当前值相等
* @param targetName
*/
static equalFor(targetName: string): ValidatorFn {
return (control: AbstractControl): {[key: string]: any} | null => {
const target = control.root.get(targetName);
if (target === null) {
return null;
}
if (this.isEmptyInputValue(control.value)) {
return null;
}
if (target.value === control.value) {
const errors = target.errors;
delete errors['equalto'];
if (this.isEmptyObject(errors)) {
target.setErrors(null);
} else {
target.setErrors(errors);
}
return null;
}
target.setErrors({ 'equalto': { valid: false } });
};
}
/**
* 验证手机号
* @returns {(ctrl: FormControl) => {mobile: {valid: boolean}}}
*/
static get mobile() {
return (control: AbstractControl) => {
if (this.isEmptyInputValue(control.value)) {
return null;
}
const valid = G.REGEX.MOBILE.test(control.value);
return valid ? null : {
'mobile': {
valid: false
}
};
};
}
/**
* 验证身份证
* @returns {(ctrl: FormControl) => {idCard: {valid: boolean}}}
*/
static get idCard() {
return (control: AbstractControl) => {
if (this.isEmptyInputValue(control.value)) {
return null;
}
const valid = G.REGEX.ID_CARD.test(control.value);
return valid ? null : {
'idcard': {
valid: false
}
};
};
}
/**
* 验证汉字
* @returns {(ctrl: FormControl) => {cn: {valid: boolean}}}
*/
static get cn() {
return (control: AbstractControl) => {
if (this.isEmptyInputValue(control.value)) {
return null;
}
const valid = G.REGEX.CN.test(control.value);
return valid ? null : {
'cn': {
valid: false
}
};
};
}
/**
* 指定个数数字
* @param {number} length
* @returns {(ctrl: FormControl) => (null | {number: {valid: boolean}})}
*/
static number(length: number = 6) {
return (control: AbstractControl) => {
if (this.isEmptyInputValue(control.value)) {
return null;
}
const valid = new RegExp(`^\\d{${length}}$`).test(control.value);
return valid ? null : {
'number': {
valid: false
}
};
};
}
/**
* 强密码（必须包含数字字母）
* @returns {(ctrl: FormControl) => (null | {number: {valid: boolean}})}
*/
static get strictPass() {
return (control: AbstractControl) => {
if (this.isEmptyInputValue(control.value)) {
return null;
}
const valid = G.REGEX.STRICT_PASS.test(control.value);
return valid ? null : {
'strictpass': {
valid: false
}
};
};
}
}