When designing a web site, it is occasionally necessary to redirect a user to another URL to the one they have tried to access.
This can normally be accomplished using HTTP redirect, however sometimes they just arent applicable or you would prefer to do it with PHP, for example:
- If a page is undergoing some maintenance and you wish to redirect users to an error page.
- As part of a PHP conditional IF statement you want to redirect to another page, perhaps you want to check if a user is logged in yet and if not redirect to the login prompt.
I am sure the are many other reasons that escape me at the time of writing for why you may wish to do this.
Fortunately PHP does provide a means to allow web designers to take this control. This task is accomplished by manipulating the header of a web page before it has been served. In order to redirect a page to an alternative URL replace the contents of the file with:
Note that if any output has been written to the browser (including HTML tags) this approach will not work, it must be either the only or the first output in the file. Therefore if you want to use it as part of a conditional logic test put that at the start of the file, for example:
<?PHPÂ
IF(loggedIn == TRUE){Â ?>
…HTML output can go here
<?PHP
}ELSE{
header( ‘Location: http://www.yourURL.com’ ) ;
}
?>
This technique is an easy way to control the flow of control in a browser based PHP application. Generally if you wish to always redirect one URL to another you should use a HTTP redirect, but a PHP redirect is also an option.
This tip was brought to you by the Web Design Team at Techita.
