Script or snippet to disallow "<" or ">"

I have a site that allows people create a text profile. There is a TEXTAREA field and I've noticed that it also allows people to insert HTML; any HTML!

Does anyone know of a script, webpage, tutorial, or code snippet that would show how to limit their input to JUST TEXT. No markup. I was thinking just killing the "<" and ">" and replacing them with "..."

Please help.

Thanks!

 

str_replace() or htmlentities() or htmlspecialchars() function

 

Here's a very robust script in PHP

/**
 * Remove HTML tags, including invisible text such as style and
 * script code, and embedded objects.  Add line breaks around
 * block-level tags to prevent word joining after tag removal.
 */
function strip_html_tags( $text )
{
    $text = preg_replace(
        array(
          // Remove invisible content
            '@<head[^>]*?>.*?</head>@siu',
            '@<style[^>]*?>.*?</style>@siu',
            '@<script[^>]*?.*?</script>@siu',
            '@<object[^>]*?.*?</object>@siu',
            '@<embed[^>]*?.*?</embed>@siu',
            '@<applet[^>]*?.*?</applet>@siu',
            '@<noframes[^>]*?.*?</noframes>@siu',
            '@<noscript[^>]*?.*?</noscript>@siu',
            '@<noembed[^>]*?.*?</noembed>@siu',
          // Add line breaks before and after blocks
            '@</?((address)|(blockquote)|(center)|(del))@iu',
            '@</?((div)|(h[1-9])|(ins)|(isindex)|(p)|(pre))@iu',
            '@</?((dir)|(dl)|(dt)|(dd)|(li)|(menu)|(ol)|(ul))@iu',
            '@</?((table)|(th)|(td)|(caption))@iu',
            '@</?((form)|(button)|(fieldset)|(legend)|(input))@iu',
            '@</?((label)|(select)|(optgroup)|(option)|(textarea))@iu',
            '@</?((frameset)|(frame)|(iframe))@iu',
        ),
        array(
            ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ',
            "\n\$0", "\n\$0", "\n\$0", "\n\$0", "\n\$0", "\n\$0",
            "\n\$0", "\n\$0",
        ),
        $text );
    return strip_tags( $text );
}

Code (markup):

For more info: http://nadeausoftware.com/articles/2007/09/php_tip_how_strip_html_tags_web_page

 

there are plenty of scripts out there that does input filtering(that's basicly what you want to do)
go to php classes(phpclasses.org) and search for "php input filter".. there's a class there that does the job for you.

if you want a full featured app( rather than a class), the one i use is html purified.. (can't remember the utl off hand.. just google it)..
if you are using smarty as a template engine the {strip}{/strip} tags will strip all html tags for you..

 

strip_tags from PHP