react-native-validator-form

Validation component for react-native forms

Simple form validation component for React-Native inspired by formsy-react. Web version: react-material-ui-form-validator

Unfortunately I don't have Mac, so this library is tested only on Android.

Supported types:

• TextInput

Default validation rules:

• matchRegexp
• isEmail
• isEmpty
• required
• trim
• isNumber
• isFloat
• isPositive
• minNumber
• maxNumber
• minFloat
• maxFloat
• minStringLength
• maxStringLength
• isString

Some rules can accept extra parameter, example:

<TextValidator
   {...someProps}
   validators={['minNumber:0', 'maxNumber:255', 'matchRegexp:^[0-9]$']}
/>

Example

Usage

 
import React from 'react';
import { Button } from 'react-native';
import { Form, TextValidator } from 'react-native-validator-form';
 
class MyForm extends React.Component {
    state = {
        email: '',
    }
 
    handleChange = (email) => {
        this.setState({ email });
    }
 
    submit = () => {
        // your submit logic
    }
 
    handleSubmit = () => {
        this.refs.form.submit();
    }
 
    render() {
        const { email } = this.state;
        return (
            <Form
                ref="form"
                onSubmit={this.handleSubmit}
            >
                <TextValidator
                    name="email"
                    label="email"
                    validators={['required', 'isEmail']}
                    errorMessages={['This field is required', 'Email invalid']}
                    placeholder="Your email"
                    type="text"
                    keyboardType="email-address"
                    value={email}
                    onChangeText={this.handleChange}
                />
                 <Button
                    title="Submit"
                    onPress={this.handleSubmit}
                />
            </Form>
        );
    }
}
 

You can add your own rules

Form.addValidationRule('isPasswordMatch', (value) => {
    if (value !== this.state.user.password) {
        return false;
    }
    return true;
});

And remove them

componentWillUnmount() {
    Form.removeValidationRule('isPasswordMatch');
}

Usage

import React from 'react';
import { Button } from 'react-native';
import { Form, TextValidator } from 'react-native-validator-form';
 
class ResetPasswordForm extends React.Component {
    state = {
        user: {},
    }
 
    componentWillMount() {
        // custom rule will have name 'isPasswordMatch'
        Form.addValidationRule('isPasswordMatch', (value) => {
            if (value !== this.state.user.password) {
                return false;
            }
            return true;
        });
    }
 
    componentWillUnmount() {
        Form.removeValidationRule('isPasswordMatch');
    }
 
    handlePassword = (event) => {
        const { user } = this.state;
        user.password = event.nativeEvent.text;
        this.setState({ user });
    }
 
    handleRepeatPassword = (event) => {
        const { user } = this.state;
        user.repeatPassword = event.nativeEvent.text;
        this.setState({ user });
    }
 
    submit = () => {
        // your submit logic
    }
 
    handleSubmit = () => {
        this.refs.form.submit();
    }
 
    render() {
        const { user } = this.state;
        return (
            <Form
                ref="form"
                onSubmit={this.handleSubmit}
            >
                <TextValidator
                    name="password"
                    label="text"
                    secureTextEntry
                    validators={['required']}
                    errorMessages={['This field is required']}
                    type="text"
                    value={user.password}
                    onChange={this.handlePassword}
                />
                <TextValidator
                    name="repeatPassword"
                    label="text"
                    secureTextEntry
                    validators={['isPasswordMatch','required']}
                    errorMessages={['Password mismatch','This field is required']}
                    type="text"
                    value={user.repeatPassword}
                    onChange={this.handleRepeatPassword}
                />
                <Button
                    title="Submit"
                    onPress={this.handleSubmit}
                />
            </Form>
        );
    }
}

Advanced usage

API

Form

• Props

Prop	Required	Type	Default value	Description
onSubmit	true	function		Callback for form that fires when all validations are passed
instantValidate	false	bool	true	If true, form will be validated after each field change. If false, form will be validated only after clicking submit button.
onError	false	function		Callback for form that fires when some of validations are not passed. It will return array of elements which not valid.
debounceTime	false	number	0	Debounce time for validation i.e. your validation will run after debounceTime ms when you stop changing your input

• Methods

Name	Params	Return	Descriptipon
resetValidations			Reset validation messages for all validated inputs
isFormValid	dryRun: bool (default true)	Promise	Get form validation state in a Promise (true if whole form is valid). Run with dryRun = false to show validation errors on form

All validated fields (Input)

• Props

Prop	Required	Type	Default value	Description
validators	false	array		Array of validators. See list of default validators above.
errorMessages	false	array		Array of error messages. Order of messages should be the same as validators prop.
name	true	string		Name of input
errorStyle	false	object	{ container: { top: 0, left: 0, position: 'absolute' }, text: { color: 'red' }, underlineValidColor: 'gray', underlineInvalidColor: 'red' } }	Error styles
validatorListener	false	function		It triggers after each validation. It will return true or false
withRequiredValidator	false	bool		Allow to use required validator in any validation trigger, not only form submit

• Methods

Name	Params	Return	Descriptipon
getErrorMessage			Get error validation message
validate	value: any, includeRequired: bool		Run validation for current component
isValid		bool	Return current validation state
makeInvalid			Set invalid validation state
makeValid			Set valid validation state

Contributing

This component covers all my needs, but feel free to contribute.