react-simple-captcha

React Simple Captcha

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

Install

$ npm install react-simple-captcha

Demo
Demo can be seen here.

Usage Guide

Just follow these 4 easy steps to use the react simple captcha:

• 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)

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 want captcha to be reloaded if user enter the wrong value then set second parameter to false validateCaptcha(user_captcha_value, false)

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

Optional Changes

Options	All of these changes are optionals
< LoadCanvasTemplate reloadText="Reload My Captcha" />	If you want to change the "Reload Captcha" with your own text
< LoadCanvasTemplate reloadColor="red" />	If you want to change the blue color of "Reload Captcha"
< LoadCanvasTemplate reloadText="Reload My Captcha" reloadColor="red" />	If you want to change the "Reload Captcha" text and it's blue color
loadCaptchaEnginge(Number_Of_Captcha_Charcters, Background_Color);	If you want to change the background color from black to your custom color. Example Syntax to change the background color to red use: loadCaptchaEnginge(6,'red');
loadCaptchaEnginge(Number_Of_Captcha_Charcters, Background_Color, Font_Color);	If you want to change the font color from white to your custom color. Example Syntax to change the font color to blue use: loadCaptchaEnginge(6,'','blue');
loadCaptchaEnginge(Number_Of_Captcha_Charcters, Background_Color, Font_Color);	If you want to change the both background and font color. Example Syntax to change the background color to white and font color to black use: loadCaptchaEnginge(6,'white','black');
loadCaptchaEnginge(Number_Of_Captcha_Charcters, Background_Color, Font_Color, Upper_Characters_Only);	If you want only upper characters and numbers use loadCaptchaEnginge(6,'','','upper');
loadCaptchaEnginge(Number_Of_Captcha_Charcters, Background_Color, Font_Color, Lower_Characters_Only);	If you want only lower characters and numbers use loadCaptchaEnginge(6,'','','lower');
loadCaptchaEnginge(Number_Of_Captcha_Charcters, Background_Color, Font_Color, Numbers);	If you want only numbers use loadCaptchaEnginge(6,'','','numbers');
loadCaptchaEnginge(Number_Of_Captcha_Charcters, Background_Color, Font_Color, Special_Characters);	If you want only special characters use loadCaptchaEnginge(6,'','','special_char');

Example

Let's create a class name CaptchaTest 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'));

Common Issues

Not Woking on ReactJS Version 18^
Solution Here: https://github.com/masroorejaz/react-simple-captcha/issues/23

Not Woking on Next.js
Solution Here: https://github.com/masroorejaz/react-simple-captcha/issues/32

Not Woking with TypeScript
Solution Here: https://github.com/masroorejaz/react-simple-captcha/issues/33

Support Me

https://www.buymeacoffee.com/masroorejaz

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 if you have any questions!