How to Create Custom Plugins in WordPress

A theme can also change a site's functionality, while a plugin can make alterations to its appearance. If there’s one cardinal rule in WordPress development, it’s this: Don’t touch WordPress core. This means that you don’t edit core WordPress files to add functionality to your site.

This is because, when it updates to a new version, it overwrites all the core files. Any functionality you want to add should therefore be added through plugins using approved WordPress APIs. If you have a great idea for a plugin but need some help creating it, try the below code. Easily we Create WP Custom Plugins.

Below are the steps to create a custom plugin in WordPress:

• Create a new folder for Your plugin: Create Folder in Wp-content/plugins/New Folder (contact-details)
• Create the main PHP file for Your plugin (contact-details.php)
• Setup Your plugin's information: Open the file in a text editor, and paste the following information in it:

<?php
/*
Plugin Name: Contact Details
Description: A test plugin to demonstrate WordPress functionality
Author: Sumita Dey
Version: 0.1
*/
add_action('admin_menu', 'contact_details_setup_menu');
function contact_details_setup_menu(){   
        add_menu_page( 'Contact Details Page', 'Contact Details', 'manage_options', 'contact_details', 'contact_details_init' );		
}
function contact_details_init(){
/*get  results form table*/
global $wpdb;
   if(isset($_POST)){
   $table = wp_form_creating;
$row_id=array( 'id' => $_POST['id'] );
$success=$wpdb->update( $table, $_POST,$row_id);
}
$customers = $wpdb->get_results("SELECT * FROM wp_contact_form;");
echo '<div id="status_msg"></div><table class="profile-table table-bordered">
<tr>
 <th>Name</th>
<th>E-mail</th>
<th>Subject</th>
 <th>Message</th>
<th>Action</th>
 </tr>';
foreach($customers as $customer){
echo '<tr onclick="opendata('.$customer->id.')">';
  $htm='<td>'.$customer->name.'</td>
 <td>'.$customer->email.'</td>
   //Important part
  <td>'.$customer->subject.'</td>
 <td>'.$customer->comment.'</td>';
echo $htm;
//Important section
echo '</tr>';
   }
echo '</table>' ;
function admin_registration_head_css() {
 $siteurl = get_option('siteurl');
$url = $siteurl . '/wp-content/plugins/' . basename(dirname(__FILE__)) . '/css/styles.css';
//Important section
$url1 = $siteurl . '/wp-content/plugins/' . basename(dirname(__FILE__)) . '/js/my.js';
echo "<link rel='stylesheet' type='text/css' href='$url' />\n";
echo '<script type="text/javascript" src="https://code.jquery.com/jquery-1.11.3.min.js"></script>';
//Important section
echo "<script type='text/javascript' src='$url1'></script>";
}
add_action('admin_head', 'admin_registration_head_css');
?>

Conclusion:

This is very important part in WP plugin development. I personally wrote the above code and it is tested by me. Please share your views in the comment section. See you on my next blog.