functions.php

<?php
/************************************CODE-1***************************************
* @Author: Boutros AbiChedid 
* @Date:   January 16, 2012
* @Websites: http://bacsoftwareconsulting.com/ ; http://blueoliveonline.com/
* @Description: Displays the Number of times Posts are Viewed on Your Blog.
* Function: Sets, Tracks and Displays the Count of Post Views (Post View Counter)
* Code is browser and JavaScript independent.
* @Tested on: WordPress version 3.2.1 
*********************************************************************************/
//Set the Post Custom Field in the WP dashboard as Name/Value pair 
function bac_PostViews($post_ID) {
 
    //Set the name of the Posts Custom Field.
    $count_key = 'post_views_count'; 
     
    //Returns values of the custom field with the specified key from the specified post.
    $count = get_post_meta($post_ID, $count_key, true);
     
    //If the the Post Custom Field value is empty. 
    if($count == ''){
        $count = 0; // set the counter to zero.
         
        //Delete all custom fields with the specified key from the specified post. 
        delete_post_meta($post_ID, $count_key);
         
        //Add a custom (meta) field (Name/value)to the specified post.
        add_post_meta($post_ID, $count_key, '0');
        return $count . ' View';
     
    //If the the Post Custom Field value is NOT empty.
    }else{
        $count++; //increment the counter by 1.
        //Update the value of an existing meta key (custom field) for the specified post.
        update_post_meta($post_ID, $count_key, $count);
         
        //If statement, is just to have the singular form 'View' for the value '1'
        if($count == '1'){
        return $count . ' View';
        }
        //In all other cases return (count) Views
        else {
        return $count . ' Views';
        }
    }
}
?>

single.php

<?php if(function_exists('bac_PostViews')) { 
    echo bac_PostViews(get_the_ID()); 
}?>

สำหรับหน้ารวมบทความ (content.php หรือ index.php ) ให้ใช้โค๊ดด้านล่างนี้เพื่อแสดงจำนวน Views ของแต่ละบทความ (แสดงอย่างเดียว ไม่อัพเดทจำนวน Views)

<?php echo (int) get_post_meta(get_the_ID(), 'post_views_count', true) . ' View(s)'; ?>

หาต้องการแสดงคอร์ลัมน์ view ในส่วนของ Admin Dashboard ให้เพิ่มโค๊ดด้านล่างนี้เข้าไปในไฟล์ function.php

<?php
/*********************************CODE-3********************************************
* @Author: Boutros AbiChedid 
* @Date:   January 16, 2012
* @Websites: http://bacsoftwareconsulting.com/ ; http://blueoliveonline.com/
* @Description: Adds a Non-Sortable 'Views' Columnn to the Post Tab in WP dashboard.
* This code requires CODE-1(and CODE-2) as a prerequesite.
* Code is browser and JavaScript independent.
* @Tested on: WordPress version 3.2.1
***********************************************************************************/
 
//Gets the  number of Post Views to be used later.
function get_PostViews($post_ID){
    $count_key = 'post_views_count';
    //Returns values of the custom field with the specified key from the specified post.
    $count = get_post_meta($post_ID, $count_key, true);
 
    return $count;
}
 
//Function that Adds a 'Views' Column to your Posts tab in WordPress Dashboard.
function post_column_views($newcolumn){
    //Retrieves the translated string, if translation exists, and assign it to the 'default' array.
    $newcolumn['post_views'] = __('Views');
    return $newcolumn;
}
 
//Function that Populates the 'Views' Column with the number of views count.
function post_custom_column_views($column_name, $id){
     
    if($column_name === 'post_views'){
        // Display the Post View Count of the current post.
        // get_the_ID() - Returns the numeric ID of the current post.
        echo get_PostViews(get_the_ID());
    }
}
//Hooks a function to a specific filter action.
//applied to the list of columns to print on the manage posts screen.
add_filter('manage_posts_columns', 'post_column_views');
 
//Hooks a function to a specific action. 
//allows you to add custom columns to the list post/custom post type pages.
//'10' default: specify the function's priority.
//and '2' is the number of the functions' arguments.
add_action('manage_posts_custom_column', 'post_custom_column_views',10,2);
?>

ดูเพิ่มเติม :
http://bacsoftwareconsulting.com/blog/index.php/wordpress-cat/how-to-track-and-display-post-views-count-in-wordpress-without-a-plugin/