比较验证器中与angular2的字段

Etse 发表于 Dev

醚

我正在尝试在Angular2中创建具有“重复密码”功能的注册表。我希望使用自定义验证器作为表单控件来工作。

我遇到的问题是，当验证程序运行时，“ this-context”似乎已设置为验证程序，因此我无法访问RegistrationForm类上的任何本地方法。而且我似乎找不到从验证器访问ControlGroup的任何好方法。

有谁知道在自定义验证器中访问同一控件组中其他控件的好方法？

是该组件的简短示例：

import { Component, View } from 'angular2/angular2';
import { Validators, ControlGroup, Control, FORM_DIRECTIVES, FORM_BINDINGS } from 'angular2/angular2';

@Component({
    selector: 'form-registration'
})
@View({
    directives: [FORM_DIRECTIVES, ROUTER_DIRECTIVES],
    template: `
        <form (submit)="register($event)" [ng-form-model]="registerForm">
            <label for="password1">Password:</label>
            <input id="password1" ng-control="password1" type="password" placeholder="Passord" />

            <label for="password2">Repeat password:</label>
            <input id="password2" ng-control="password2" type="password" placeholder="Gjenta passord" />

            <button class="knapp-submit" type="submit" [disabled]="!registerForm.valid">Registrer deg</button>
        </form>
    `
})
export class RegistrationForm {
    registerForm: ControlGroup;

    constructor() {            
        this.registerForm = new ControlGroup({
            password1: new Control('', Validators.required),
            password2: new Control('', this.customValidator)
        });
    }

    public register(event: Event) {
        // submit form
    }

    private customValidator(control: Control) {
        // check if control is equal to the password1 control
        return {isEqual: control.value === this.registerForm.controls['password1'].value};
    }
}

醚

因此，我通过将customValidator绑定到类的此上下文来解决该问题，如Sergio的评论中所述。

请记住，.bind（this）函数返回具有绑定上下文的新函数实例。

import { Component, View } from 'angular2/angular2';
import { Validators, ControlGroup, Control, FORM_DIRECTIVES, FORM_BINDINGS } from 'angular2/angular2';

@Component({
    selector: 'form-registration'
})
@View({
    directives: [FORM_DIRECTIVES, ROUTER_DIRECTIVES],
    template: `...my form template...`
})
export class RegistrationForm {
    registerForm: ControlGroup;

    constructor() {           
        this.customValidator = this.customValidator.bind(this); 
        this.registerForm = new ControlGroup({
            password1: new Control('', Validators.required),
            password2: new Control('', this.customValidator)
        });
    }

    public register(event: Event) {
        // submit form
    }

    private customValidator(control: Control) {
        // check if control is equal to the password1 control
        return {isEqual: control.value === this.registerForm.controls['password1'].value};
    }
}