React-form-validator-hook NPM

React-validator

GitHub repository

react-form-validator-hook

Installation

 npm i react-form-validator-hook

Usage

import React, {useState} from 'react';
import useValidator from 'react-form-validator-hook';

// Create a configuration object containing the rules for each field

const config = {
  name: {
    rules: {
        required: {
          message: 'Name is required',
        },
        minLength: {
          value: 3,
          message: 'Name must be at least 3 characters long',
        },
        maxLength: {
          value: 20,
          message: 'Name must be at most 20 characters long',
        },
    }
  },
  email: {
    rules: {
        required: {
            message: 'Email is required',
        },
        email: {
            message: 'Email is invalid',
        }
    }
  },
  password: {
      rules: {
          password: true,
          required: {
              message: "Password is required"
          },
          // For password validation you can use the following rules if you want to activate them you must set the value to an object containing an error message, otherwise if you want to deactivate them you must set the value to false
          minLengthPassword: {
              value: 8,
              message: "Password must be at least 8 characters long"
          },
          number: {
              message: "Password must contain at least one number"
          },
          upperCase: {
              message: "Password must contain at least one uppercase letter"
          },
          lowerCase: {
              message: "Password must contain at least one lowercase letter"
          },
          specialChar: false,
          error: {
              message: "Password must contain at least one number, one uppercase letter and one lowercase letter"
          }
      }
  },
  passwordConfirm: {
      rules: {
          required: {
              message: "Password confirmation is required"
          },
          confirm: {
              field: "password",
              message: "Password confirmation does not match password"
          }
      }
  }
};

const Form = () => {
    
    const initialValues = {
        name: '',
        email: '',
        password: '',
        passwordConfirm: ''
    };

    const {
        values,
        errors,
        handleValueChange,
        validateOnSubmit,
        PasswordValidationComponent,
        ErrorComponent,
    } = useValidator(initialValues, config);
    
    const handleChange = (e) => {
        const { name, value } = e.target;
        handleValueChange(name, value); 
    };
    
    return (
        <form onSubmit={validateOnSubmit}>
            {...}
            {
                // Error component show the errors of the field if there are any
            }
            <ErrorComponent name="name" />
            
            {
                // PasswordValidationComponent show the validation state of the password according to the rules defined in the configuration object
            }
            <PasswordValidationComponent />
        </form>
    )
}

export default Form;

Note: The PasswordValidationComponent component is optional and is used to display the validation state of the password according to the rules defined in the configuration object.
The ErrorComponent component is optional and is used to display the errors of the field if there are any.
The validateOnSubmit function is used to validate the form when submitting.
The handleValueChange function is used to update the value of the field and validate it.
The values object contains the values of the fields.
The errors object contains the errors of the fields.
The config object contains the rules for each field.
The initialValues object contains the initial values of the fields.
The name attribute of the field must be the same as the key of the field in the config object.
The message attribute of the rule is used to display a custom error message if none passed no message will be displayed.
The error attribute of password rule is used to display a custom error message if password does not match the password rules set.
The confirm attribute of passwordConfirm rule is used to check if the password matches the password confirmation field he need a field prop in order to know the confirmed field name and compare their value.

Configuration parameters

Rules

Rule	Description	Type	Default
required	Check if the field is empty	{ message: string }	false
email	Check if the field is email	{ message: string }	false
minLength	Check if the field is at least the minimum length	{ value: number, message: string }	undefined
maxLength	Check if the field is at most the maximum length	{ value: number, message: string }	undefined
min	Check if the field is at least the minimum value `input type number only`	{ value: number, message: string }	undefined
max	Check if the field is at most the maximum value `input type number only`	{ value: number, message: string }	undefined
pattern	Check if the field matches the regular expression	{ value: RegExp, message: string }	undefined
password	Define the field as password and activate the verification of password params (number, upperCase, lowerCase, specialChar & minLengthPassword) `password only`	boolean	undefined
number	Check if the field contains at least one number `password only`	{ message: string } \| false	false
upperCase	Check if the field contains at least one uppercase letter `password only`	{ message: string } \| false	false
lowerCase	Check if the field contains at least one lowercase letter `password only`	{ message: string } \| false	false
specialChar	Check if the field contains at least one special character `password only`	{ message: string } \| false	false
confirm	Check if the field matches the field passed in the field prop (need to match the verified field name) `verification field only`	{ field: string, message: string }	undefined
error	Display a custom error message if password does not match the password rules set `password only`	{ message: string }	undefined