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<title>Creating a Web Application</title>
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<div class="section">
<div class="titlepage"><div><div><h2 class="title" style="clear: both">
<a name="libzeep.webapp"></a><a class="link" href="webapp.html" title="Creating a Web Application">Creating a Web Application</a>
</h2></div></div></div>
<div class="toc"><dl>
<dt><span class="section"><a href="webapp.html#libzeep.webapp.intro">Introduction</a></span></dt>
<dt><span class="section"><a href="webapp.html#libzeep.webapp.basics">The building blocks</a></span></dt>
<dt><span class="section"><a href="webapp.html#libzeep.webapp.hello">Hello world!</a></span></dt>
<dt><span class="section"><a href="webapp.html#libzeep.webapp.forms">Using forms</a></span></dt>
<dt><span class="section"><a href="webapp.html#libzeep.webapp.el">Using <code class="computeroutput"><span class="identifier">el</span></code>
script</a></span></dt>
<dt><span class="section"><a href="webapp.html#libzeep.webapp.processing_tags">Processing Tags</a></span></dt>
</dl></div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="libzeep.webapp.intro"></a><a class="link" href="webapp.html#libzeep.webapp.intro" title="Introduction">Introduction</a>
</h3></div></div></div>
<p>
This section will guide you through all the code you have to write to create
an interactive web application using libzeep. The way this works in libzeep
looks a lot like popular frameworks found for Java. If you're familiar with
JSP and e.g. Struts, you'll notice the similarities.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="libzeep.webapp.basics"></a><a class="link" href="webapp.html#libzeep.webapp.basics" title="The building blocks">The building blocks</a>
</h3></div></div></div>
<p>
It is very inconvenient to write HTML code in C++ directly using string concatenations
and streams. Therefore, a separation has been made. All HTML is put into
XHTML template files. These template files can use special tags to generate
HTML tags based on data provided by the server application. A script language
that looks a lot like JSP 'Expression Language' (or <code class="literal">el</code>
in short) is used to program conditional constructs. Communication between
this <code class="literal">el</code> script and the server application is done via
<code class="literal">el::object</code> data objects.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="libzeep.webapp.hello"></a><a class="link" href="webapp.html#libzeep.webapp.hello" title="Hello world!">Hello world!</a>
</h3></div></div></div>
<p>
Let's start with a simple hello world example. We first create a template
file, save this file as <code class="literal">hello.xhtml</code>.
</p>
<pre class="programlisting"><?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xhtml PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/1999/xhtml">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>Hello</title>
</head>
<body>
<p>Hello, world!</p>
</body>
</html>
</pre>
<p>
This is a very simple, strict XHTML 1.1 file. We will serve it with our server:
</p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">zeep</span><span class="special">/</span><span class="identifier">http</span><span class="special">/</span><span class="identifier">webapp</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bind</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">std</span><span class="special">;</span>
<span class="keyword">class</span> <span class="identifier">MyWebApp</span> <span class="special">:</span> <span class="keyword">public</span> <code class="computeroutput"><a class="link" href="../zeep/http/webapp.html" title="Class webapp">zeep::http::webapp</a></code>
<span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
<span class="identifier">MyWebApp</span><span class="special">();</span>
<span class="keyword">void</span> <span class="identifier">handle_welcome</span><span class="special">(</span><span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/request.html" title="Struct request">zeep::http::request</a></code><span class="special">&</span> <span class="identifier">request</span><span class="special">,</span>
<span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code><span class="special">&</span> <span class="identifier">scope</span><span class="special">,</span> <code class="computeroutput"><a class="link" href="../zeep/http/reply.html" title="Class reply">zeep::http::reply</a></code><span class="special">&</span> <span class="identifier">reply</span><span class="special">);</span>
<span class="special">};</span>
<span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">MyWebApp</span><span class="special">()</span>
<span class="special">{</span>
<span class="identifier">mount</span><span class="special">(</span><span class="string">""</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">handle_welcome</span><span class="special">,</span> <span class="keyword">this</span><span class="special">,</span> <span class="identifier">_1</span><span class="special">,</span> <span class="identifier">_2</span><span class="special">,</span> <span class="identifier">_3</span><span class="special">));</span>
<span class="special">}</span>
<span class="keyword">void</span> <span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">handle_welcome</span><span class="special">(</span><span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/request.html" title="Struct request">zeep::http::request</a></code><span class="special">&</span> <span class="identifier">request</span><span class="special">,</span>
<span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code><span class="special">&</span> <span class="identifier">scope</span><span class="special">,</span> <code class="computeroutput"><a class="link" href="../zeep/http/reply.html" title="Class reply">zeep::http::reply</a></code><span class="special">&</span> <span class="identifier">reply</span><span class="special">)</span>
<span class="special">{</span>
<span class="identifier">create_reply_from_template</span><span class="special">(</span><span class="string">"hello.xhtml"</span><span class="special">,</span> <span class="identifier">scope</span><span class="special">,</span> <span class="identifier">reply</span><span class="special">);</span>
<span class="special">}</span>
<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
<span class="special">{</span>
<span class="identifier">MyWebApp</span> <span class="identifier">server</span><span class="special">;</span>
<span class="identifier">server</span><span class="special">.</span><span class="identifier">bind</span><span class="special">(</span><span class="string">"0.0.0.0"</span><span class="special">,</span> <span class="number">80</span><span class="special">);</span>
<span class="identifier">server</span><span class="special">.</span><span class="identifier">run</span><span class="special">(</span><span class="number">1</span><span class="special">);</span>
<span class="special">}</span>
</pre>
<p>
By calling <code class="computeroutput"><span class="identifier">mount</span></code> with the
empty string, we tell libzeep to redirect all access to the base URL to handle_welcome.
This means that visiting the URL <a href="http://localhost/" target="_top">http://localhost/</a>
should now return a page containing the string 'Hello, world!'.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="libzeep.webapp.forms"></a><a class="link" href="webapp.html#libzeep.webapp.forms" title="Using forms">Using forms</a>
</h3></div></div></div>
<p>
Now lets create a form to pass some data from the browser to the server and
back. Save the following file as <code class="literal">form.xhtml</code>.
</p>
<pre class="programlisting"><?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xhtml PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/1999/xhtml">
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:zeep="http://www.cmbi.ru.nl/libzeep/ml">
<head>
<title>Form example</title>
</head>
<body>
<zeep:if test="${name}">
<p>Hello ${name}!</p>
</zeep:if>
<p>Please enter your name and press the Submit button</p>
<form id="myForm" action="salute" method="get">
<label>Name: <input id="name" type="text" name="name" value="${name}"/></label>
<input type="submit" value="Submit" />
</form>
</body>
</html>
</pre>
<p>
We add the zeep prefix to our html tag, it has the value <code class="literal">"http://www.cmbi.ru.nl/libzeep/ml"</code>
which is the same as the default value for the <code class="computeroutput">ns</code> parameter
in the <code class="computeroutput"><a class="link" href="../zeep/http/webapp.html" title="Class webapp">zeep::http::webapp</a></code>
constructor. Note that the input tag has an attribute with value '${data}'.
This is a piece of expression language script. This will be explained below:
</p>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">zeep</span><span class="special">/</span><span class="identifier">http</span><span class="special">/</span><span class="identifier">webapp</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">zeep</span><span class="special">/</span><span class="identifier">http</span><span class="special">/</span><span class="identifier">webapp</span><span class="special">/</span><span class="identifier">el</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">bind</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
<span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">std</span><span class="special">;</span>
<span class="keyword">class</span> <span class="identifier">MyWebApp</span> <span class="special">:</span> <span class="keyword">public</span> <code class="computeroutput"><a class="link" href="../zeep/http/webapp.html" title="Class webapp">zeep::http::webapp</a></code>
<span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
<span class="identifier">MyWebApp</span><span class="special">();</span>
<span class="keyword">void</span> <span class="identifier">handle_welcome</span><span class="special">(</span><span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/request.html" title="Struct request">zeep::http::request</a></code><span class="special">&</span> <span class="identifier">request</span><span class="special">,</span>
<span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code><span class="special">&</span> <span class="identifier">scope</span><span class="special">,</span> <code class="computeroutput"><a class="link" href="../zeep/http/reply.html" title="Class reply">zeep::http::reply</a></code><span class="special">&</span> <span class="identifier">reply</span><span class="special">);</span>
<span class="keyword">void</span> <span class="identifier">handle_salute</span><span class="special">(</span><span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/request.html" title="Struct request">zeep::http::request</a></code><span class="special">&</span> <span class="identifier">request</span><span class="special">,</span>
<span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code><span class="special">&</span> <span class="identifier">scope</span><span class="special">,</span> <code class="computeroutput"><a class="link" href="../zeep/http/reply.html" title="Class reply">zeep::http::reply</a></code><span class="special">&</span> <span class="identifier">reply</span><span class="special">);</span>
<span class="special">};</span>
<span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">MyWebApp</span><span class="special">()</span>
<span class="special">{</span>
<span class="identifier">mount</span><span class="special">(</span><span class="string">""</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">handle_welcome</span><span class="special">,</span> <span class="keyword">this</span><span class="special">,</span> <span class="identifier">_1</span><span class="special">,</span> <span class="identifier">_2</span><span class="special">,</span> <span class="identifier">_3</span><span class="special">));</span>
<span class="identifier">mount</span><span class="special">(</span><span class="string">"salute"</span><span class="special">,</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">bind</span><span class="special">(&</span><span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">handle_salute</span><span class="special">,</span> <span class="keyword">this</span><span class="special">,</span> <span class="identifier">_1</span><span class="special">,</span> <span class="identifier">_2</span><span class="special">,</span> <span class="identifier">_3</span><span class="special">));</span>
<span class="special">}</span>
<span class="keyword">void</span> <span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">handle_welcome</span><span class="special">(</span><span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/request.html" title="Struct request">zeep::http::request</a></code><span class="special">&</span> <span class="identifier">request</span><span class="special">,</span>
<span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code><span class="special">&</span> <span class="identifier">scope</span><span class="special">,</span> <code class="computeroutput"><a class="link" href="../zeep/http/reply.html" title="Class reply">zeep::http::reply</a></code><span class="special">&</span> <span class="identifier">reply</span><span class="special">)</span>
<span class="special">{</span>
<span class="identifier">create_reply_from_template</span><span class="special">(</span><span class="string">"form.xhtml"</span><span class="special">,</span> <span class="identifier">scope</span><span class="special">,</span> <span class="identifier">reply</span><span class="special">);</span>
<span class="special">}</span>
<span class="keyword">void</span> <span class="identifier">MyWebApp</span><span class="special">::</span><span class="identifier">handle_salute</span><span class="special">(</span><span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/request.html" title="Struct request">zeep::http::request</a></code><span class="special">&</span> <span class="identifier">request</span><span class="special">,</span>
<span class="keyword">const</span> <code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code><span class="special">&</span> <span class="identifier">scope</span><span class="special">,</span> <code class="computeroutput"><a class="link" href="../zeep/http/reply.html" title="Class reply">zeep::http::reply</a></code><span class="special">&</span> <span class="identifier">reply</span><span class="special">)</span>
<span class="special">{</span>
<span class="identifier">zeep</span><span class="special">::</span><span class="identifier">http</span><span class="special">::</span><span class="identifier">parameter_map</span> <span class="identifier">params</span><span class="special">;</span>
<span class="identifier">get_parameters</span><span class="special">(</span><span class="identifier">scope</span><span class="special">,</span> <span class="identifier">params</span><span class="special">);</span>
<span class="identifier">string</span> <span class="identifier">name</span> <span class="special">=</span> <span class="identifier">params</span><span class="special">.</span><span class="identifier">get</span><span class="special">(</span><span class="string">"name"</span><span class="special">,</span> <span class="string">""</span><span class="special">).</span><span class="identifier">as</span><span class="special"><</span><span class="identifier">string</span><span class="special">>();</span>
<code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code> <span class="identifier">sub</span><span class="special">(</span><span class="identifier">scope</span><span class="special">);</span>
<span class="identifier">sub</span><span class="special">.</span><span class="identifier">put</span><span class="special">(</span><span class="string">"name"</span><span class="special">,</span> <span class="identifier">name</span><span class="special">);</span>
<span class="identifier">create_reply_from_template</span><span class="special">(</span><span class="string">"form.xhtml"</span><span class="special">,</span> <span class="identifier">sub</span><span class="special">,</span> <span class="identifier">reply</span><span class="special">);</span>
<span class="special">}</span>
<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
<span class="special">{</span>
<span class="identifier">MyWebApp</span> <span class="identifier">server</span><span class="special">;</span>
<span class="identifier">server</span><span class="special">.</span><span class="identifier">bind</span><span class="special">(</span><span class="string">"0.0.0.0"</span><span class="special">,</span> <span class="number">80</span><span class="special">);</span>
<span class="identifier">server</span><span class="special">.</span><span class="identifier">run</span><span class="special">(</span><span class="number">1</span><span class="special">);</span>
<span class="special">}</span>
</pre>
<p>
This time, we add a new handler for the 'salute' page. The form has an action
that points to this salute page. As can be seen in the <code class="computeroutput"><span class="identifier">handle_salute</span></code>
method, we first collect the parameters passed in. Parameters are accessed
by name. We then create a sub scope of the scope passed in. In this sub scope
we put the value of the parameter so that the XHTML processor can access
it. And then we return a reply based on the contents of the <code class="literal">form.xhtml</code>
template and the contents of the sub scope we created.
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="libzeep.webapp.el"></a><a class="link" href="webapp.html#libzeep.webapp.el" title="Using el script">Using <code class="computeroutput"><span class="identifier">el</span></code>
script</a>
</h3></div></div></div>
<p>
<code class="computeroutput"><span class="identifier">el</span></code> means <span class="emphasis"><em>Expression
Language</em></span>. It is a script language that tries to be like <a href="http://en.wikipedia.org/wiki/Unified_Expression_Language" target="_top">http://en.wikipedia.org/wiki/Unified_Expression_Language</a>.
The objects can be created in the C++ server code using the <code class="computeroutput"><a class="link" href="../zeep/http/el/object.html" title="Class object">zeep::http::el::object</a></code>
class. Object created this way are then stored in an <code class="computeroutput"><a class="link" href="../zeep/http/el/scope.html" title="Class scope">zeep::http::el::scope</a></code>
object and passed along to the XHTML processing code.
</p>
<p>
<code class="computeroutput"><a class="link" href="../zeep/http/el/object.html" title="Class object">zeep::http::el::object</a></code> objects can contain
simple data and arrays. E.g., to create an array you could write:
</p>
<pre class="programlisting"><span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">zeep</span><span class="special">::</span><span class="identifier">http</span><span class="special">;</span>
<span class="identifier">vector</span><span class="special"><</span><span class="identifier">el</span><span class="special">::</span><span class="identifier">object</span><span class="special">></span> <span class="identifier">ints</span><span class="special">;</span>
<span class="keyword">for</span> <span class="special">(</span><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> <span class="identifier">i</span> <span class="special"><</span> <span class="number">10</span><span class="special">;</span> <span class="special">++</span><span class="identifier">i</span><span class="special">)</span>
<span class="special">{</span>
<span class="identifier">el</span><span class="special">::</span><span class="identifier">object</span> <span class="identifier">int_object</span><span class="special">;</span>
<span class="identifier">int_object</span><span class="special">[</span><span class="string">"value"</span><span class="special">]</span> <span class="special">=</span> <span class="identifier">i</span><span class="special">;</span>
<span class="identifier">ints</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">int_object</span><span class="special">);</span>
<span class="special">}</span>
<span class="identifier">scope</span><span class="special">.</span><span class="identifier">put</span><span class="special">(</span><span class="string">"ints"</span><span class="special">,</span> <span class="identifier">el</span><span class="special">::</span><span class="identifier">object</span><span class="special">(</span><span class="identifier">ints</span><span class="special">));</span>
</pre>
<p>
And then you can access this in the XHTML:
</p>
<pre class="programlisting">1: ${ints[1].value}, 2: ${ints[2].value}
</pre>
<p>
Which should output "1: 1, 2: 2"
</p>
</div>
<div class="section">
<div class="titlepage"><div><div><h3 class="title">
<a name="libzeep.webapp.processing_tags"></a><a class="link" href="webapp.html#libzeep.webapp.processing_tags" title="Processing Tags">Processing Tags</a>
</h3></div></div></div>
<p>
The method <code class="computeroutput"><span class="identifier">create_reply_from_template</span></code>
takes the name of a template file and a scope to generate the output XHTML.
We've already seen that <code class="computeroutput"><span class="identifier">el</span></code>
scripts are processed by this method. But there is more, several special
tags in the template are processed in a special way. These tags are in a
separate XML namespace. You can change this name space using the <code class="computeroutput"><span class="identifier">ns</span></code> parameter in the <code class="computeroutput"><a class="link" href="../zeep/http/webapp.html" title="Class webapp">zeep::http::webapp</a></code> constructor, the default
is <code class="literal">http://www.cmbi.ru.nl/libzeep/ml</code>.
</p>
<p>
In the template for the form example above you might have noticed the <code class="literal"><zeep:if></code>
tag. This tag takes one attribute called <code class="computeroutput"><span class="identifier">test</span></code>
and the value of this tag is interpreted as a <code class="computeroutput"><span class="identifier">el</span></code>
script. If the script evaluates to something other than empty, zero or false,
the content of the <code class="literal"><zeep:if></code> tag is included, otherwise
it is discarded in the output.
</p>
<p>
There are several predefined processing tags which are summarized below.
You can also add your own processing tags using the <code class="computeroutput"><a class="link" href="../zeep/http/webapp.html#idp7720512-bb">zeep::http::webapp::add_processor</a></code> method. This
method takes a <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code> parameter for the name of the tag
and a <code class="computeroutput"><span class="identifier">processor_type</span></code> parameter
which is a call back function.
</p>
<div class="table">
<a name="libzeep.webapp.processing_tags.list_of_predefined_processing_tags"></a><p class="title"><b>Table 1. List of predefined processing tags</b></p>
<div class="table-contents"><table class="table" summary="List of predefined processing tags">
<colgroup>
<col>
<col>
<col>
</colgroup>
<thead><tr>
<th>
<p>
tag name (without prefix)
</p>
</th>
<th>
<p>
Description
</p>
</th>
<th>
<p>
Example
</p>
</th>
</tr></thead>
<tbody>
<tr>
<td>
<p>
include
</p>
</td>
<td>
<p>
Takes one parameter named <code class="computeroutput"><span class="identifier">file</span></code>
and replaces the tag with the processed content of this file
</p>
</td>
<td>
<p>
<code class="literal"><zeep:include file="menu.xhtml"/></code>
</p>
</td>
</tr>
<tr>
<td>
<p>
if
</p>
</td>
<td>
<p>
Takes one parameter named <code class="computeroutput"><span class="identifier">test</span></code>
containing an <code class="computeroutput"><span class="identifier">el</span></code>
script. This script is evaluated and if the result is not empty,
zero or false, the content of the <code class="computeroutput"><span class="keyword">if</span></code>
tags is inserted in the output. Otherwise, the content is discarded.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:if test="${not empty name}">
Hello ${name}
</zeep:if>
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
iterate
</p>
</td>
<td>
<p>
Takes two parameters, <code class="computeroutput">collection</code> which contains an
<code class="computeroutput">el</code> script that evaluates to an array <code class="computeroutput">el::object</code>
and a name in <code class="computeroutput">var</code>. The content of the <code class="computeroutput">iterate</code>
tag is included for each value of <code class="computeroutput">collection</code> and
<code class="computeroutput">var</code> will contain the current value.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><ul><zeep:iterate collection="${names}" var="name">
<li>${name}</li>
</zeep:iterate></ul>
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
for
</p>
</td>
<td>
<p>
Takes three parameters. The parameters <code class="computeroutput">begin</code> and
<code class="computeroutput">end</code> should evaluate to a number. The parameter <code class="computeroutput">var</code>
contains a name that will be used to hold the current value when
inserting the content of the <code class="computeroutput">for</code> tag in each iteration
of the for loop between <code class="computeroutput">begin</code> and <code class="computeroutput">end</code>.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:for begin="1" end="3" var="i">
${i},
</zeep:for>
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
number
</p>
</td>
<td>
<p>
Format the number in the <code class="computeroutput">n</code> parameter using the <code class="computeroutput">f</code>
format. This is limited to the formats <code class="literal">'#.##0'</code>
and <code class="literal">'#.##0B'</code> for now. The first formats an integer
value using thousand separators, the second tries to format the
integer value in a power of two multiplier (kibi, mebi, etc.) with
a suffix of <code class="computeroutput">B</code>, <code class="computeroutput">M</code>, <code class="computeroutput">G</code>, etc.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:number n="1024" f="0.00#B"/>
Will output 1K
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
options
</p>
</td>
<td>
<p>
This tag will insert multiple <code class="literal"><option></code>
tags for each element in the <code class="computeroutput">collection</code> parameter.
This <code class="computeroutput">collection</code> paramter can contain an array of strings
or it can contain an array of <code class="computeroutput">el::object</code>. In the latter
case, you can specify a <code class="computeroutput">value</code> and <code class="computeroutput">label</code>
parameter to name the value and label fields of these objects.
A <code class="computeroutput">selected</code> parameter can be used to select the current
value of the options.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:options collection="${names}"
value="id" label="fullName" selected="1" />
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
option
</p>
</td>
<td>
<p>
Generate a single <code class="literal"><option></code> tag with a
value as specified in the <code class="computeroutput">value</code> parameter. If <code class="computeroutput">selected</code>
evaluates to the same value as <code class="computeroutput">value</code>, the option is
selected. The content of the <code class="literal"><option></code>
tag is inserted in the final tag.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:option value="1" selected="${user}">
John Doe
</zeep:option>
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
checkbox
</p>
</td>
<td>
<p>
Create an <code class="literal"><input></code> tag with type <code class="computeroutput">checkbox</code>.
The parameter <code class="computeroutput">name</code> is used as name attribute and the
parameter <code class="computeroutput">checked</code> is evaluated to see if the checkbox
should be in checked mode.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:checkbox name='cb1' checked='${true}'>
Check me
</zeep:checkbox>
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
url
</p>
</td>
<td>
<p>
The url processing tag creates a new variable in the current scope
with the name as specified in the <code class="computeroutput">var</code> parameter. It
then creates a list of all original HTTP parameters for the current
page. You can override these parameter, and add new ones, by adding
<code class="literal"><param></code> tags in the <code class="literal"><url></code>
tag.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:url var="next">
<zeep:param name='page' value='${page + 1}'/>
<zeep:url>
<a href="${next}">Next page</a>
</pre>
<p>
</p>
</td>
</tr>
<tr>
<td>
<p>
param
</p>
</td>
<td>
<p>
see <code class="literal">url</code> above.
</p>
</td>
<td class="auto-generated"> </td>
</tr>
<tr>
<td>
<p>
embed
</p>
</td>
<td>
<p>
This tag takes the content of the <code class="computeroutput">var</code> parameter which
should contain valid XML and puts the processed value in the document.
</p>
</td>
<td>
<p>
</p>
<pre class="programlisting"><zeep:embed var="&lt;em&gt;hello, world!&lt;/em&gt;"/>
</pre>
<p>
</p>
</td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break">
</div>
</div>
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
<td align="left"></td>
<td align="right"><div class="copyright-footer">Copyright © 2012 Maarten L. Hekkelman<p>
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
</p>
</div></td>
</tr></table>
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