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<h1>TClientScriptLoader</h1>

<com:DocLink ClassPath="System.Web.UI.WebControls.TClientScriptLoader" />

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<p class="block-content">
The <tt>TClientScriptLoader</tt> publish a collection of javascript files as assets.
For example, suppose we have a directory name "<tt>mylib</tt>" in
the <tt>protected/pages</tt> directory of our application.</p>
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assets/
protected/
  pages/
    mylib/
       file1.js 
       file2.js
       file3.js
       file4.js
       packages.php
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<p class="block-content">The <tt>PackagePath</tt> property can be an existing asset directory
or a namespace path to the directory containing javascript files.
For example, to publish the javascript files in the <tt>mylib</tt>
directory, we can specify the <tt>PackagePath</tt> as follows.
The first tag <tt>TClientScriptLoader</tt> relies on the asset template tag and 
assumes that the page template containing the <tt>TClientScriptLoader</tt> tag instance
is in the <tt>protected/pages</tt> directory.
The second <tt>TClientScriptLoader</tt> tag uses the namespace notation to 
specify the path.
</p>

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&lt;com:TClientScriptLoader PackagePath=&lt;%~ mylib %&gt; /&gt;
&lt;com:TClientScriptLoader PackagePath="Application.pages.mylib" /&gt;
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<p class="block-content">
When the files in the <tt>PackagePath</tt> are published as assets, a script loader
 php file "<tt>clientscripts.php</tt>" is automatically copied 
 to that asset directory.
 The script loader, combines multiple javascript files and serve up as gzip if possible.
</p>
<h2>Grouping Javascript Files</h2>
<p class="block-content">
Allowable scripts and script dependencies can be grouped by using a "<tt>packages.php</tt>" file
with the following format. This "<tt>packages.php</tt>" is optional, if absent the file names
without ".js" extension are used. The "<tt>packages.php</tt>" must be in the directory given by
<tt>PackagePath</tt>.
</p>

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&lt;?php
 $packages = array(
    'package1' => array('file1.js', 'file2.js'),
    'package2' => array('file3.js', 'file4.js'));

 $deps = array(
    'package1' => array('package1'),
    'package2' => array('package1', 'package2')); //package2 requires package1 first.

 return array($packages,$deps); //must return $packages and $deps in an array
?&gt;
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<p class="block-content">The first element of the array returned by the <tt>packages.php</tt> should
contain an array of javascripts files relative to the <tt>packages.php</tt>
that corresponds to a particular grouping. For example, in the above <tt>packages.php</tt>,
the grouping '<tt>package1</tt>' combines two javascript files, namely, '<tt>file1.js</tt>'
and '<tt>file2.js</tt>'.
</p>

<p class="block-content">The second element of the array returned by the <tt>packages.php</tt> should
contain an array of grouping dependencies ordered in the way that the groups should be combined.
For example, grouping '<tt>package1</tt>' only depends on the '<tt>package1</tt>' grouping files 
(i.e. '<tt>file1.js</tt>' and '<tt>file2.js</tt>'). While '<tt>package2</tt>' depends
on both '<tt>package1</tt>' and '<tt>package2</tt>' groupings. That is, '<tt>package2</tt>'
will combine, in order, '<tt>file1.js</tt>', '<tt>file2.js</tt>', '<tt>file3.js</tt>', and '<tt>file4.js</tt>'.
</p>

<h2>Loading Javascript Packages</h2>

<p class="block-content">To load a particular javascript file or package, set the <tt>PackageScripts</tt> 
property with value '<tt>package1</tt>' to load the '<tt>package1</tt>' scripts. 
A maximum of 25 packages separated by commas is allowed.
Dependencies of the packages are automatically resolved by the script loader php file.
</p>

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&lt;com:TClientScriptLoader PackagePath=&lt;%~ mylib %&gt; PackageScripts="package2" /&gt;
&lt;script type="text/javascript"&gt;
 //javascript code utilizing javascript code loaded in 'package2' above
&lt;/script&gt;
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<p>Each <tt>&lt;com:TClientScriptLoader&gt;</tt> generates an HTML <tt>&lt;script&gt;</tt>
element to load the required javascript files.</p>

<h2>Removing Javascript Comments</h2>
<p class="block-content">The <tt>DebugMode</tt> property when false
removes comments and white spaces from the published javascript files. If
the <tt>DebugMode</tt> property is not set, the debug mode is determined from the 
<a href="?page=Advanced.Performance">application mode</a>.
</p>
<div class="note"><b class="note">Note:</b>
If the <tt>DebugMode</tt> is false either explicitly or when the application mode is non-debug,
then cache headers are also sent to inform the browser and proxies to cache the file.
Moreover, the post-processed (comments removed and zipped) are saved in the assets
directory for the next requests. That is, in non-debug mode the scripts are cached
in the assets directory until they are deleted.
</div>

<h2>Compressing Javascript with GZip</h2>
<p class="block-content">
The <tt>EnableGzip</tt> property (default is true) enables the
published javascripts to be served as zipped if the browser and php server allows it.
</p>
<div class="last-modified">$Id: ClientScript.page 1650 2007-01-24 06:55:32Z wei $</div>

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