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Validator

npm Package @angular/forms
Module import { Validator } from '@angular/forms';
Source forms/src/directives/validators.ts

Interface Overview

      
      interface Validator { 
  validate(c: AbstractControl): ValidationErrors | null
  registerOnValidatorChange(fn: () => void)?: void
}

Description

An interface that can be implemented by classes that can act as validators.

Usage

      
      @Directive({
  selector: '[custom-validator]',
  providers: [{provide: NG_VALIDATORS, useExisting: CustomValidatorDirective, multi: true}]
})
class CustomValidatorDirective implements Validator {
  validate(c: Control): {[key: string]: any} {
    return {"custom": true};
  }
}

Child Interfaces

Members

      
      validate(c: AbstractControl): ValidationErrors | null
    
      
      registerOnValidatorChange(fn: () => void)?: void