If you are building an application where you allow your users to input content through and HTML editor, often they will simply copy and paste from Word or other applications that might add some weird tags which might endup breaking your layout or causing the content not to display as expected.

One solution is to clean the content prior to displaying it or prior to posting it into the database. Eitherway, the resulting content will display with only the chosen HTML tags, thus giving you more control on the final display to your visitors and removing all junk code that nobody wants and that could cause display headaches for you.

<?php
 $sampletext = '<b>Some bold content</b> <a href="">Test</a><h3>some more text</h3><p>More content here</p>';

echo strip_tags($sampletext);
 //The above code usses the built in PHP function strip_tags, which will remove/strip all tags.

 echo strip_tags($sampletext, '<p><a><h3>');
 //The above code uses the same built in PHP strip_tags function, but we added some exceptions to it.   Any tag listed as an exception will not be removed/striped.
?>

As you can see it is pretty easy to control what tags get stripped and which ones do not.

You can also apply the same strip_tags function prior to posting to a MySQL database, so that the content will be saved only with the enabled tags you allow or no tags if you did not specify any exceptions.

No matter if you use the function prior to posting to your database or after, it will save many headaches and you will retain control of the display of the content on the site and prevent other script from breaking due to junk code.

A very easy way to redirect users to another page is by using the following code:

<?php
header('Location: http://urltosenduserto.com/somepage.php');
// Just replace the http://urltosenduserto.com/somepage.php
// with the URL of any page or site you want to forward the user to.
 ?>

That’s it, as you can see this is pretty simple. Just make sure that this code is added to the top of your page before any other header information is passed, otherwise it might not work properly.

Many web applications often require the ability to automatically send out notifications through email to members or site owners.  

PHP makes it very easy to achive this using the built-in mail function as demonstrated in the code below:

<?php

// BELOW WE SET THE TO: FIELD
// This is where the email message will be sent to.

$to = "youremail@somedomain.com";

// BELOW WE SET THE SUBJECT AND MESSAGE
// Pretty self explanatory.  These are the Subject
// and Message of the email you want to send out.

$subject = "Your Email Subject";
$message = "Write your email message text in here.";

// BELOW WE SETUP THE HEADER OF THE EMAIL MESSAGE.

$headers = "From: TypeYourName";
$headers .= "Reply-To:" 'test@yourdomain.com'."\r\n";
$headers .= "Return-Path:" 'test@yourdomain.com'. "\r\n";
$headers .= "X-Mailer: PHP5\n";
$headers .= 'MIME-Version: 1.0' . "\n";
$headers .= 'Content-type: text/html; charset=iso-8859-1' . "\r\n";
mail($to,$subject,$message,$headers);
?>

 
That’s it, it is that simple.

For advanced PHP programmers, you can easily replace the subject, message, to, from fields and other portions of the above code to pull the information from a database in order to send multiple emails or more customized messages.

For now we just want to cover the basics and might add another post at a later time to expand deeper into what can be done using the PHP mail capabilities.