The document discusses cookies, which are small files stored on a client's computer that track user information and can be used to personalize web pages. Cookies can be set using the setcookie() or header() functions before any output is generated. The setcookie() syntax includes parameters for the cookie name, value, expiration time, path, domain, and security. An example is provided to set a cookie called "Product" with a value of "Car" that expires in one hour. Methods for checking if a cookie is set and deleting a cookie are also outlined.

1. Aruna Devi P.
Assistant Professor
Department of Computer Science(SF)
V.V.V. College for Women

2. Cookies
 Small File – Max size 4KB
 Stored on client
 Used for tracking user information
 Could be retrieved to personalize the page when users
visit for next time.
 Could be read by the domain which sets the cookie

3. Setting Cookie
 Setting of cookie could be done with
 setcookie() function
 header() function
 This function should be used before any output is
generated from the script
 Otherwise Cookie will not be set

4. Syntax for Cookie
 setcookie(Name, Value, Expire, Path, Domain, Security)
 Name: It is used to set the name of the cookie.
 Value: It is used to set the value of the cookie.
 Expire: It is used to set the expiry timestamp of the cookie
after which the cookie can’t be accessed.
 Path: It is used to specify the path on the server for which
the cookie will be available.
 Domain: It is used to specify the domain for which the
cookie is available.
 Security: It is used to indicate that the cookie should be
sent only if a secure HTTPS connection exists.

5. Example
 setcookie(“Product”, ”Car”, time()+3600, “/”,
“.yourdomain.com”,0)
 Ist two parameter is the name and value of the cookie
 Next is the time() which retrieves the current time, when we
add 3600 sec the expiry time will be one hour from the cookie
setting
 / says the cookie could be retrieved from any page within the
server environment.
 Domain is the site which we are working, if left blank then it
would be considered as localhost
 Last argument is for transmitting cookie in secure or unsecure
environment (Secure =1, unsecure =0).

6. header() function
 header(“Set-Cookie: Product = Car;
expires = Thu, 12-Dec-19 12:30: 59 GMT;
path=/;
domain=yourdomain.com”);
This method is difficult since we have to create a header
string.
Time is mentioned in Unix epoch format.

7. Checking the setting of cookie
 isset() is used whether a cookie has been set
 $_COOKIE is the superglobal for retrieving the cookie
value.
 isset($_COOKIE[“cookiename”])
 Returns true if the cookiename specified is set
 Returns false if the cookiename is not set
 To print the value of the cookie
 echo “Cookie value is : “.$_COOKIE[“cookiename”]

8. Deleting a Cookie
 Could be deleted in two ways
 Using setcookie() is called with the name of cookie
 setcookie(“cookiename”)
 Change the timestamp to the time that already expired.
 setcookie(“cookiename”, “”,time()-60,”/”,domain,0)

9. Thank you