React Simple Captcha

React Simple Captcha is a very powerful and easy to use captcha for React JS.

Install

$ npm install react-simple-captcha

Demo
Demo can be seen here.

Usage Guide

• Step 1:

Import all functions from react-simple-captcha

import { loadCaptchaEnginge, LoadCanvasTemplate, LoadCanvasTemplateNoReload, validateCaptcha } from 'react-simple-captcha';

• Step 2:

Place < LoadCanvasTemplate /> or < LoadCanvasTemplateNoReload /> (if you do not want 'Reload Captcha' functionality) in your render code

render() {
     return (<div>
        <LoadCanvasTemplate />
         </div>);
 };

OR

render() {
     return (<div>
         <LoadCanvasTemplateNoReload />
         </div>);
 };

• Step 3:

Paste loadCaptchaEnginge(6) (You can change 6 to number of captcha charcters you want) in componentDidMount

componentDidMount () {
    loadCaptchaEnginge(6); 
 };

• Step 4:

Validate captcha by using validateCaptcha(user_captcha_value)

<!-- Let's create a function doSubmit() which submit user value onClick() (See Example section below for details) -->  

doSubmit = () => {
<!-- Let's assume there is an HTML input text box with id 'user_captcha_input' to get user input -->   
     let user_captcha_value = document.getElementById('user_captcha_input').value;

     if (validateCaptcha(user_captcha_value)==true) {
         alert('Captcha Matched');
     }

     else {
         alert('Captcha Does Not Match');
     }
 };

OR
If you don't watch captcha to be reloaded if user enter the wrong value then set second parameter to false validateCaptcha(user_captcha_value, false)

<!-- Let's create a function doSubmit() which submit user value onClick() (See Example section below for details) -->  
   
doSubmit = () => {
<! -- Let's assume there is an HTML input text box with id 'user_captcha_input' to get user input -->    
       let user_captcha_value = document.getElementById('user_captcha_input').value;

       if (validateCaptcha(user_captcha_value, false)==true) {
           alert('Captcha Matched');
       }

       else {
           alert('Captcha Does Not Match');
       }
   };

Options

Listed are all the options available for react-simple-captcha

| Name | Description | | ------ | ------ | | < LoadCanvasTemplate /> | It will load the captcha with 'Reload Captcha' functionality. Place between your render code, usage example < LoadCanvasTemplate /> | | < LoadCanvasTemplateNoReload /> | It will load the captcha without 'Reload Captcha' functionality. Place between your render code, usage example < LoadCanvasTemplateNoReload /> | | loadCaptchaEnginge(Number_Of_Captcha_Charcters); | Simply paste it in componentDidMount(). Pass number of captcha characters you want to display. | | validateCaptcha(User_Submitted_Value) | Will return true if user submitted value matches with captcha otherwise false. Also will reload captcha if user submitted value is false | | validateCaptcha(User_Submitted_Value, false) | Will return true if user submitted value matches with captcha otherwise false. Will not reload captcha if user submitted value is false |

Example

Let's create a class name CaptchaTest (and save it as captcha_test.jsx in src folder) with react simple captcha functionality:

import React, { Component } from 'react';
import { loadCaptchaEnginge, LoadCanvasTemplate, LoadCanvasTemplateNoReload, validateCaptcha } from 'react-simple-captcha';



class CaptchaTest extends Component {

   componentDidMount () {
      loadCaptchaEnginge(6); 
   };

   doSubmit = () => {
       let user_captcha = document.getElementById('user_captcha_input').value;

       if (validateCaptcha(user_captcha)==true) {
           alert('Captcha Matched');
           loadCaptchaEnginge(6); 
           document.getElementById('user_captcha_input').value = "";
       }

       else {
           alert('Captcha Does Not Match');
           document.getElementById('user_captcha_input').value = "";
       }
   };

   render() {
        

       return (<div>
           <div className="container">
               <div className="form-group">

                   <div className="col mt-3">
                       <LoadCanvasTemplate />
                   </div>

                   <div className="col mt-3">
                       <div><input placeholder="Enter Captcha Value" id="user_captcha_input" name="user_captcha_input" type="text"></input></div>
                   </div>

                   <div className="col mt-3">
                       <div><button class="btn btn-primary" onClick={() => this.doSubmit()}>Submit</button></div>
                   </div>
                     
               </div>

           </div>
       </div>);
   };
}

export default CaptchaTest;

Import CaptchaTest in index.js

import CaptchaTest from './captcha_test'; 

Now replace ReactDOM.render with

ReactDOM.render(<CaptchaTest />, document.getElementById('root'));

Browser support

Works in every modern browser which has support for canvas element.

License

react-simple-captcha is licensed under the MIT license.

Developer Profile

Name: Masroor Ejaz
Linkedin: https://www.linkedin.com/in/masroorejaz/
Twitter: https://twitter.com/masroorejaz
Note: Feel free to contact me it you have any questions!