React Form Validator
React Form Validator exposes a single React component which uses the render prop pattern to validate the input on its child form.
It is built as a pure React component, with no additional dependencies, making it efficient and cheap to add to any React project. Due to interacting with underlying basic HTML tags, it is compatible with popular design Frameworks like Semantic or Bootstrap out of the box.
Table of Contents
Installation
Usage
Project Motivation
Additional Info
Installation
NPM/YARN
yarn add react-validator-component
import { Validator } from 'react-validator-component'
Clone
git clone git@github.com:JDLT-Ltd/react-form-validator-component.git
Usage
Example
class ExampleForm extends React.Component {
constructor(props) {
super(props)
this.state = {
fields: {
emailAddress: {
rules: ['isEmail', 'isRequired']
}
}
}
}
render() {
return (
<Validator fields={this.state.fields} parent={this}>
{({ isFormValid, fields, onChange, errors }) => {
return (
<form>
<label>Your Emails</label>
<input name="emailAddress" onChange={onChange} />
{errors.emailAddress.map((error, i) => {
return <span key={i}>{error}</span>
})}
{isFormValid && <button type="submit">Submit</button>}
</form>
)
}}
</Validator>
)
}
}
Props in RFVC
Required props
Validator
has one required props
fields
- an object with one property per input field
The key to each property must match the name
attribute of the input field it refers to, and its value is an object with one property: a rules
array of any combination of strings referring to our predefined validation rules and user-defined custom rules.
Optional Props
It also has three optional props
parent
- a reference to the component whose state Validator
should add validated form data to.
By default a property will be added to parent
's state with a key equal to the name
attribute of its input
and a value equal to the valid input.onValidate
- A handler defining what to do with validated input.
By default, Validator
will set parent.state[fieldName]
to be either valid input or null if input is invalid.
You need to provide at least one of parent
or onValidate
validateOnLoad
- a boolean
If validateOnLoad
is true, Validator
will attempt to validate every field that is prepopulated on componentDidMount
. (empty fields will not dsiplay errors - however they will prevent set isFormValid to false)
Rules in RFVC
RFVC let's you use a mixture of predefined rules and your personal custom rules, just as it let's you provide your own functionality for onPassValidation
.
Default Rules
fields: {
emailAddress: {
rules: ['isEmail', 'isRequired']
}
}
We are currently still working on creating a comprehensive list of default rules, please check src/lib/rules.js
for now.
Custom Rules
fields: {
emailAddress: {
rules: [
'isEmail',
{
validator: data => {
if (data) return true
return false
},
error: 'Please provide a value'
}
]
}
}
You can write custom rules and simply use them inside the rules Array as long as they follow RFVC's format of
{
validator: {Your Code},
error: {Your Error Message}
}
Where validator
is a function returning a boolean and error
is the desired error message.
Arguments
The following arguments are provided to the render prop function:
isFormValid
A boolean. true
when all inputs are validated.
isFieldValid
An object with a property for each field which will be true
if it's valid and false
if it's not.
fields
An array of objects which can optionally be used in the render prop function to build your form using a map. Each object will contain within its value
property all properties that were passed into Validator
.
i.e.
fields: {
emailAddress: {
rules: ['isEmail', 'isRequired'],
label: 'email address'
}
}
becomes
;[
{
key: 'emailAddress',
value: {
rules: ['isEmail', 'isRequired'],
label: 'email address'
}
}
]
onChange
onChange
will validate the input provided and then update the parent components state, adding any valid input and removing possible invalid input.
errors
Validator
will also provide an errors
object, which contains a key for each validated input, the value of which is an array containing all applicable errors.
These can be displayed as a group or be mapped in order to produce individual error labels.