How to add php code in wordpress page

 There are several ways for adding php code in wordpress pages.

1. Plugins

You can use code snippets plugin in word press. I myself prefer to have more control on the code.So generally I used to avoid plugin and rather write some php code manually. Here I am going to show you both the options.

 Go to plugins tab

Search for code snippets plugin

Install and activate the plugin. After activating you will see a new snippet text appear on the left of the website. click on the snippet and add any php code to it

2. Without Plugin

In wordpress there is a concept of short code. You can call  any php code with the help of short code. short code can directly be used in the wordpress website pages. short code can be mapped to any function.

 add_shortcode('show_post', 'get_all_post');

We have created a short code with name show_post and mapped it to a php function to get all the posts from data base. You can write any php code inside the function depending on your need.

Write the function inside functions.php file. wordpress searches for the shortcode and call it's mapped function.

function get_all_post(){
	global $wpdb;
	$tablename=$wpdb->prefix.''posts";
	ob_start();
	$posts= $wpdb->get_results( $wpdb->prepare("SELECT title FROM $tablename"));
	?>
    <?php
	foreach( $posts as $post) {?>
    <div class='show-title'>
		   <article><h1>
			<?php echo $post->title; 
			   ?>
			</h1></article>
    </div>
    <?php
	}
	return ob_get_clean();
}

In functions.php you can define above php function and return the output.

• wpdb is the global variable in wordpress to access the database
• wpdb-prefix is the prefix default db prefix. you can modify this prefix value also or you can mention your own prefix
• wpdb->get_results to fetch the results from db according to query you have mentioned

One thing to remember here is never echo or print any statement inside the shortcode function in wordpress. Always try to return the output. Shortcode function should always return the output as then only it will be shown on your website at expected location otherwise the function will print the output before the code gets executed completely. 

In above function you can see we are also returning the HTML content from the function.

For returning html code from wordpress shortcode function.

• close the php code with ?> symbol and then start writing your html code
• use <?php for again starting php code in you function

Putting shortcode in your wordpress website page

 [show_post]

This is how you can put the shortcode in any of your wordpress website page. Function mapped to this shortcode will get executed by itself. This shortcode an we used in multiple website pages

This is how your complete function in functions.php should looks like.

function get_all_post(){
	global $wpdb;
	$tablename=$wpdb->prefix.''posts";
	ob_start();
	$posts= $wpdb->get_results( $wpdb->prepare("SELECT title FROM $tablename"));
	?>
    <?php
	foreach( $posts as $post) {?>
    <div class='show-title'>
		   <article><h1>
			<?php echo $post->title; 
			   ?>
			</h1></article>
    </div>
    <?php
	}
	return ob_get_clean();
}
add_shortcode('show_post', 'get_all_post');

Hope above article will be helpful for you 

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