How to Set, Read and Delete Cookie using JavaScript

This tutorial helps and teaches you how to Set, Read and Delete Cookie using JavaScript.

Cookies are a technology which can be easily and simply used by a Webmaster to achieve a great and many useful tasks when creating websites.
Although cookies are well known to users, many people are not really sure what they are used for, and a large amount of webmasters don't realize the possibilities open to them when they use cookies.
Others have been put off, thinking that they must be difficult to use, but in reality, cookies can be set and used by a simple command in most scripting languages. In this tutorial I'll cover setting, reading and deleting cookies in JavaScript.

JavaScript Code:

<script type="text/javascript"> 

// Function to set a Cookie

function vpb_set_cookie(cookie_name, cookie_value, total_days_allowed) 

{

                   if (total_days_allowed != "") 

                   {

                                       var vpb_date = new Date();

                                       vpb_date.setTime(vpb_date.getTime() + (total_days_allowed*24*60*60*1000));

                                       var vpb_expires = ";

                                expires="+vpb_date.toGMTString();

                                   }

                   else { var vpb_expires = "";

                               }

                   document.cookie = cookie_name+"="+cookie_value+vpb_expires+";

                path=/";

               }

// Function to read a Cookie

function vpb_read_cookie(cookie_name) 

{

                   var vpb_cookie_name = cookie_name + "=";

                   var split_cookie_name = document.cookie.split(';

               ');

                   for( var i = 0;

                i < split_cookie_name.length;

                i++ ) 

                   {

                                       var vpb_split_cookie_name = split_cookie_name[i];

                                       while ( vpb_split_cookie_name.charAt(0)==' ' )

                                       {

                                                          vpb_split_cookie_name = vpb_split_cookie_name.substring(1,vpb_split_cookie_name.length);

                                                          if ( vpb_split_cookie_name.indexOf(vpb_cookie_name) == 0 ) 

                                                              return vpb_split_cookie_name.substring(vpb_cookie_name.length,vpb_split_cookie_name.length);

                                                      }

                                   }

                   return null;

               }

// Function to delete a Cookie

function vpb_delete_cookie(cookie_name) 

{

                   vpb_set_cookie(cookie_name, "", -1);

               }

//This is how you should use the above function to set the cookie with 10 days to keep the cookie active before it expires.

vpb_set_cookie('fullname','Victor Olu',10);

//This is how you should use the above function to delete your cookie - The cookie will be deleted if you uncomment the below code.

//vpb_delete_cookie('fullname');

//This is how you should use the above function to read or get your cookie after setting it.

alert( vpb_read_cookie('fullname') );

</script>