What are Partial Views?

I've been using Codeigniter in order to get accustomed to the Model-View-Controller architecture, and to try and speed up the process of making and implementing sites.

I keep seeing references to "Partial Views" but can't find a definition for the term.

Can anyone tell me what a partial 开发者_如何转开发view is, and where it is used?

A partial view is just a sub-view that you can include in a parent view. Let's take a look at a common example:

// Controller:
$data['myvar'] = array('element1', 'element2', 'element3');
$this->load->view('myview', $data);

// Myview:
<ul>
  foreach ($myvar as $var) {
    $this->load->view('partialview', array('var', $var));
  }
</ul>

// Partialview:
<li><?= $var ?></li>

This is useful to repeat content according to a list. Note that nothing differs between a view and a partialview, it's just the way you include it that defines the term.

The best way to describe a "partial view" is to think of it as a template, it displays a chunk of html with Model data passed to it.

Good examples of where to use one would be where you plan on displaying the same html over and over, like a menu or a page header or even better yet use them to display content requested using ajax.

Basically you call an action on the controller that returns the partial view from lets say jQuery and then put the returned markup into a select or div tag. Here is an example of doing that from my blog easy ajax with aspnet mvc and jquery, yes I know it asp.net mvc not php and codeigniter, but the principal is the same.