user_guide_src/source/helpers/html_helper.rst

###########
HTML Helper
###########

The HTML Helper file contains functions that assist in working with
HTML.

.. contents:: Page Contents

Loading this Helper
===================

This helper is loaded using the following code::

	$this->load->helper('html');

The following functions are available:

br()
====

.. php:function:: br($count = 1)

	:param	int	$count: Number of times to repeat the tag
	:returns:	string

Generates line break tags (<br />) based on the number you submit.
Example::

	echo br(3);

The above would produce: <br /><br /><br />

heading()
=========

.. php:function:: heading($data = '', $h = '1', $attributes = '')

	:param	string	$data: Content
	:param	string	$h: Heading level
	:param	array	$attributes: HTML attributes
	:returns:	string

Lets you create HTML heading tags. The first parameter will contain the
data, the second the size of the heading. Example::

	echo heading('Welcome!', 3);

The above would produce: <h3>Welcome!</h3>

Additionally, in order to add attributes to the heading tag such as HTML
classes, ids or inline styles, a third parameter is available::

	echo heading('Welcome!', 3, 'class="pink"')

The above code produces: <h3 class="pink">Welcome!<<h3>

img()
=====

.. php:function:: img($src = '', $index_page = FALSE, $attributes = '')

	:param	string	$src: Image source data
	:param	bool	$index_page: Whether to treat $src as a routed URI string
	:param	array	$attributes: HTML attributes
	:returns:	string

Lets you create HTML <img /> tags. The first parameter contains the
image source. Example::

	echo img('images/picture.jpg'); // gives <img src="http://site.com/images/picture.jpg" />

There is an optional second parameter that is a TRUE/FALSE value that
specifics if the *src* should have the page specified by
``$config['index_page']`` added to the address it creates.
Presumably, this would be if you were using a media controller::

	echo img('images/picture.jpg', TRUE); // gives <img src="http://site.com/index.php/images/picture.jpg" alt="" />


Additionally, an associative array can be passed to the ``img()`` function
for complete control over all attributes and values. If an *alt* attribute
is not provided, CodeIgniter will generate an empty string.

Example::

	$image_properties = array(               
		'src' 	=> 'images/picture.jpg',               
		'alt' 	=> 'Me, demonstrating how to eat 4 slices of pizza at one time',  
		'class' => 'post_images',               
		'width' => '200',               
		'height'=> '200',               
		'title' => 'That was quite a night',               
		'rel' 	=> 'lightbox'
	);

	img($image_properties);
	// <img src="http://site.com/index.php/images/picture.jpg" alt="Me, demonstrating how to eat 4 slices of pizza at one time" class="post_images" width="200" height="200" title="That was quite a night" rel="lightbox" />


link_tag()
==========

.. php:function:: ling_tag($href = '', $rel = 'stylesheet', $type = 'text/css', $title = '', $media = '', $index_page = FALSE)

	:param	string	$href: What are we linking to
	:param	string	$rel: Relation type
	:param	string	$type: Type of the related document
	:param	string	$title: Link title
	:param	string	$media: Media type
	:param	bool	$index_page: Whether to treat $src as a routed URI string
	:returns:	string

Lets you create HTML <link /> tags. This is useful for stylesheet links,
as well as other links. The parameters are *href*, with optional *rel*,
*type*, *title*, *media* and *index_page*.

*index_page* is a boolean value that specifies if the *href* should have
the page specified by ``$config['index_page']`` added to the address it creates.

Example::

	echo link_tag('css/mystyles.css');
	// gives <link href="http://site.com/css/mystyles.css" rel="stylesheet" type="text/css" />


Further examples::

	echo link_tag('favicon.ico', 'shortcut icon', 'image/ico');
	// <link href="http://site.com/favicon.ico" rel="shortcut icon" type="image/ico" />

	echo link_tag('feed', 'alternate', 'application/rss+xml', 'My RSS Feed');
	// <link href="http://site.com/feed" rel="alternate" type="application/rss+xml" title="My RSS Feed" />

Additionally, an associative array can be passed to the ``link()`` function
for complete control over all attributes and values::

	$link = array(               
		'href'	=> 'css/printer.css',
		'rel'	=> 'stylesheet',
		'type'	=> 'text/css',
		'media'	=> 'print'
	);

	echo link_tag($link);
	// <link href="http://site.com/css/printer.css" rel="stylesheet" type="text/css" media="print" />

nbs()
=====

.. php:function:: nbs($num = 1)

	:param	int	$num: Number of space entities to produce
	:returns:	string

Generates non-breaking spaces (&nbsp;) based on the number you submit.
Example::

	echo nbs(3);

The above would produce::

	&nbsp;&nbsp;&nbsp;

ul() and ol()
=============

.. php:function:: ul($list, $attributes = '')

	:param	array	$list: List entries
	:param	array	$attributes: HTML attributes
	:returns:	string

Permits you to generate ordered or unordered HTML lists from simple or
multi-dimensional arrays. Example::

	$list = array(
		'red',
		'blue',
		'green',
		'yellow'
	);

	$attributes = array(
		'class'	=> 'boldlist',
		'id'	=> 'mylist'
	);

	echo ul($list, $attributes);

The above code will produce this::

	 <ul class="boldlist" id="mylist">
		<li>red</li>
		<li>blue</li>
		<li>green</li>
		<li>yellow</li>
	</ul>

Here is a more complex example, using a multi-dimensional array::

	$attributes = array(
		'class'	=> 'boldlist',
		'id'	=> 'mylist'
	);

	$list = array(
		'colors'  => array(
			'red',
			'blue',
			'green'
		),
		'shapes'  => array(
			'round',
			'square',
			'circles' => array(
				'ellipse',
				'oval',
				'sphere'
			)
		),
		'moods'  => array(
			'happy',
			'upset' => array(
				'defeated' => array(
					'dejected',
					'disheartened',
					'depressed'
				),
				'annoyed',
				'cross',
				'angry'
			)
		)
	);

	echo ul($list, $attributes);

The above code will produce this::

	<ul class="boldlist" id="mylist">
		<li>colors
			<ul>
				<li>red</li>
				<li>blue</li>
				<li>green</li>
			</ul>
		</li>
		<li>shapes
			<ul>
				<li>round</li>
				<li>suare</li>
				<li>circles
					<ul>
						<li>elipse</li>
						<li>oval</li>
						<li>sphere</li>
					</ul>
				</li>
			</ul>
		</li>
		<li>moods
			<ul>
				<li>happy</li>
				<li>upset
					<ul>
						<li>defeated
							<ul>
								<li>dejected</li>
								<li>disheartened</li>
								<li>depressed</li>
							</ul>
						</li>
						<li>annoyed</li>
						<li>cross</li>
						<li>angry</li>
					</ul>
				</li>
			</ul>
		</li>
	</ul>

.. php:function:: ol($list, $attributes = '')

	:param	array	$list: List entries
	:param	array	$attributes: HTML attributes
	:returns:	string

Identical to :php:func:`ul()`, only it produces the <ol> tag for
ordered lists instead of <ul>.

meta()
======

.. php:function:: meta($name = '', $content = '', $type = 'name', $newline = "\n")

	:param	string	$name: Meta name
	:param	string	$content: Meta content
	:param	string	$type: Meta type
	:param	string	$newline: Newline character
	:returns:	string

Helps you generate meta tags. You can pass strings to the function, or
simple arrays, or multidimensional ones.

Examples::

	echo meta('description', 'My Great site');
	// Generates:  <meta name="description" content="My Great Site" />

	echo meta('Content-type', 'text/html; charset=utf-8', 'equiv');
	// Note the third parameter.  Can be "equiv" or "name"
	// Generates:  <meta http-equiv="Content-type" content="text/html; charset=utf-8" />

	echo meta(array('name' => 'robots', 'content' => 'no-cache'));
	// Generates:  <meta name="robots" content="no-cache" />

	$meta = array(
		array(
			'name' => 'robots',
			'content' => 'no-cache'
		),
		array(
			'name' => 'description',
			'content' => 'My Great Site'
		),
		array(
			'name' => 'keywords',
			'content' => 'love, passion, intrigue, deception'
		),
		array(
			'name' => 'robots',
			'content' => 'no-cache'
		),
		array(
			'name' => 'Content-type',
			'content' => 'text/html; charset=utf-8', 'type' => 'equiv'
		)
	);

	echo meta($meta);
	// Generates:
	// <meta name="robots" content="no-cache" />
	// <meta name="description" content="My Great Site" />
	// <meta name="keywords" content="love, passion, intrigue, deception" />
	// <meta name="robots" content="no-cache" />
	// <meta http-equiv="Content-type" content="text/html; charset=utf-8" />

doctype()
=========

.. php:function:: doctype($type = 'xhtml1-strict')

	:param	string	$type: Doctype name

Helps you generate document type declarations, or DTD's. XHTML 1.0
Strict is used by default, but many doctypes are available.

Example::

	echo doctype(); // <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

	echo doctype('html4-trans'); // <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">

The following is a list of doctype choices. These are configurable, and
pulled from application/config/doctypes.php

+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| Doctype                       | Option                       | Result                                                                                                                                           |
+===============================+==============================+==================================================================================================================================================+
| XHTML 1.1                     | doctype('xhtml11')           | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">                                                |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML 1.0 Strict              | doctype('xhtml1-strict')     | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">                                    |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML 1.0 Transitional        | doctype('xhtml1-trans')      | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">                        |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML 1.0 Frameset            | doctype('xhtml1-frame')      | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Frameset//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-frameset.dtd">                                |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML Basic 1.1               | doctype('xhtml-basic11')     | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.1//EN" "http://www.w3.org/TR/xhtml-basic/xhtml-basic11.dtd">                                    |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| HTML 5                        | doctype('html5')             | <!DOCTYPE html>                                                                                                                                  |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| HTML 4 Strict                 | doctype('html4-strict')      | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">                                                       |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| HTML 4 Transitional           | doctype('html4-trans')       | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">                                           |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| HTML 4 Frameset               | doctype('html4-frame')       | <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd">                                            |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| MathML 1.01                   | doctype('mathml1')	       | <!DOCTYPE math SYSTEM "http://www.w3.org/Math/DTD/mathml1/mathml.dtd">                                                                           |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| MathML 2.0                    | doctype('mathml2')           | <!DOCTYPE math PUBLIC "-//W3C//DTD MathML 2.0//EN" "http://www.w3.org/Math/DTD/mathml2/mathml2.dtd">                                             |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| SVG 1.0                       | doctype('svg10')             | <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.0//EN" "http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd">                                       |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| SVG 1.1 Full                  | doctype('svg11')             | <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">                                               |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| SVG 1.1 Basic                 | doctype('svg11-basic')       | <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1 Basic//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-basic.dtd">                                   |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| SVG 1.1 Tiny                  | doctype('svg11-tiny')        | <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1 Tiny//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-tiny.dtd">                                     |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML+MathML+SVG (XHTML host) | doctype('xhtml-math-svg-xh') | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1 plus MathML 2.0 plus SVG 1.1//EN" "http://www.w3.org/2002/04/xhtml-math-svg/xhtml-math-svg.dtd">    |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML+MathML+SVG (SVG host)   | doctype('xhtml-math-svg-sh') | <!DOCTYPE svg:svg PUBLIC "-//W3C//DTD XHTML 1.1 plus MathML 2.0 plus SVG 1.1//EN" "http://www.w3.org/2002/04/xhtml-math-svg/xhtml-math-svg.dtd"> |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML+RDFa 1.0                | doctype('xhtml-rdfa-1')      | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd">                                          |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+
| XHTML+RDFa 1.1                | doctype('xhtml-rdfa-2')      | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.1//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-2.dtd">                                          |
+-------------------------------+------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------+