php man page for strip_tags

STRIP_TAGS(3)								 1							     STRIP_TAGS(3)

strip_tags - Strip HTML and PHP tags from a string

SYNOPSIS
       string strip_tags (string  $str, [string  $allowable_tags])

DESCRIPTION
	This  function	tries to return a string with all NULL bytes, HTML and PHP tags stripped from a given $str. It uses the same tag stripping
       state machine as the fgetss(3) function.

PARAMETERS
	      o $str
		- The input string.

	      o $allowable_tags
		- You can use the optional second parameter to specify tags which should not be stripped.

	      Note

		      HTML comments and PHP tags are also stripped. This is hardcoded and can not be changed with $allowable_tags.

	      Note

		      This parameter should not contain whitespace. strip_tags(3) sees a tag as a case-insensitive string between < and the  first
		     whitespace or >.

	      Note

		      In  PHP  5.3.4 and later, you will also need to include the self-closing XHTML tag to strip these from $str. For example, to
		     strip both <br> and <br/>, you should use:

		     <?php
		     strip_tags($input, '<br><br/>');
		     ?>

RETURN VALUES
	Returns the stripped string.

CHANGELOG
       +--------+---------------------------------------------------+
       |Version |						    |
       |	|						    |
       |	|		     Description		    |
       |	|						    |
       +--------+---------------------------------------------------+
       | 5.3.4	|						    |
       |	|						    |
       |	| strip_tags(3) no longer strips self-closing XHTML |
       |	| tags	unless	the  self-closing XHTML tag is also |
       |	| given in $allowable_tags.			    |
       |	|						    |
       | 5.0.0	|						    |
       |	|						    |
       |	|	  strip_tags(3) is now binary safe.	    |
       |	|						    |
       +--------+---------------------------------------------------+
EXAMPLES
       Example #1

	      strip_tags(3) example

	      <?php
	      $text = '<p>Test paragraph.</p><!-- Comment --> <a href="#fragment">Other text</a>';
	      echo strip_tags($text);
	      echo "
";

	      // Allow <p> and <a>
	      echo strip_tags($text, '<p><a>');
	      ?>

	      The above example will output:

	      Test paragraph. Other text
	      <p>Test paragraph.</p> <a href="#fragment">Other text</a>

NOTES
       Warning

	       Because strip_tags(3) does not actually validate the HTML, partial or broken tags can result in the removal of more text/data  than
	      expected.

       Warning

	       This  function does not modify any attributes on the tags that you allow using $allowable_tags, including the style and onmouseover
	      attributes that a mischievous user may abuse when posting text that will be shown to other users.

       Note

	       Tag names within the input HTML that are greater than 1023 bytes in length will be treated as though they are  invalid,	regardless
	      of the $allowable_tags parameter.

SEE ALSO
       htmlspecialchars(3).

PHP Documentation Group 													     STRIP_TAGS(3)