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     <a class="edit-on-gh" href="https://github.com/apache/struts-site/edit/master/source/tag-developers/alt-syntax.md" title="Edit this page on GitHub">Edit on GitHub</a>

     <a href="index" title="back to Tag Developers Guide"><< back to Tag Developers Guide</a>

     <h1 id="alt-syntax">Alt Syntax</h1>

 <blockquote>
   <p>Note: As from Struts 2.6 option to disable the AltSyntax has been removed and now using %{…} is the only way
 to create an expression as stated below.</p>
 </blockquote>

 <p>The <em>altSyntax</em> is an option that can be defined in <code class="highlighter-rouge">struts.xml</code>. By default it is set to true and it is <strong>strongly</strong>
 recommend you do not change that unless you are upgrading from WebWork 2.1.7 or previous versions.</p>

 <blockquote>
   <p>You can also turn on the altSyntax on a per-page basis by using the <em>set</em> tag. Simply set the name <em>useAltSyntax</em><br />
 to the value <em>true</em> . From this point on, all tags will use the altSyntax for the rest of the request.</p>
 </blockquote>

 <p>The altSyntax changes the behavior of how tags are interpreted. Instead of evaluating each tag parameter against
 the value stack and needing single quotes to mark string literals, only marked expressions are evaluated.</p>

 <p>Example:</p>

 <p>the following code uses the <a href="tag-syntax.html">Tag Syntax</a>:</p>

 <pre><code class="language-jsp">&lt;s:iterator value="cart.items"&gt;
    ...
    &lt;s:textfield label="'Cart item No.' + #rowstatus.index + ' note'"
                  name="'cart.items[' + #rowstatus.index + '].note'"
                  value="note" /&gt;
 &lt;/s:iterator&gt;
 </code></pre>

 <p>this is somewhat counter intuitive to normal HTML tag behaviour, and you get loads of single quotes. Now the same example
 in altSyntax:</p>

 <pre><code class="language-jsp">&lt;s:iterator value="cart.items"&gt;
    ...
    &lt;s:textfield label="Cart item No. %{#rowstatus.index} note"
                  name="cart.items[%{#rowstatus.index}].note"
                  value="%{note}" /&gt;
 &lt;/s:iterator&gt;
 </code></pre>

 <p>Only expressions enclosed with <code class="highlighter-rouge">%{}</code> are evaluated. The code is shorter and clearer, very similar to JSTL EL usage.
 Quoting problems, eg. with javascript function calls, are avoided.</p>

 <p>In order to fully understand why this option exists and what the differences are, it is best to get a bit of history
 about WebWork.</p>

 <blockquote>
   <p>If you are <em>not</em> upgrading from WebWork 2.1.7 or previous versions and you don’t care about the history of WebWork’s
 evolution, you can skip this section. See the <a href="tag-syntax.html">Tag Syntax</a> section for more information
 on the standard tag syntax support</p>
 </blockquote>

 <h2 id="history">History</h2>

 <p>In WebWork 2.1.4, the altSyntax option was introduced. The book, WebWork in Action, while based around WebWork 2.1.7,
 was entirely written with the assumption that the altSyntax was enabled. As of WebWork 2.2, the altSyntax is turned
 on by default and eventually the old syntax will no longer be supported and will be removed from the code.</p>

   </section>
 </article>


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	<article class="container">
	<section class="col-md-12">
	<a class="edit-on-gh" href="https://github.com/apache/struts-site/edit/master/source/tag-developers/alt-syntax.md" title="Edit this page on GitHub">Edit on GitHub</a>

	<a href="index" title="back to Tag Developers Guide"><< back to Tag Developers Guide</a>

	<h1 id="alt-syntax">Alt Syntax</h1>

	<blockquote>
	<p>Note: As from Struts 2.6 option to disable the AltSyntax has been removed and now using %{…} is the only way
	to create an expression as stated below.</p>
	</blockquote>

	<p>The <em>altSyntax</em> is an option that can be defined in <code class="highlighter-rouge">struts.xml</code>. By default it is set to true and it is <strong>strongly</strong>
	recommend you do not change that unless you are upgrading from WebWork 2.1.7 or previous versions.</p>

	<blockquote>
	<p>You can also turn on the altSyntax on a per-page basis by using the <em>set</em> tag. Simply set the name <em>useAltSyntax</em><br />
	to the value <em>true</em> . From this point on, all tags will use the altSyntax for the rest of the request.</p>
	</blockquote>

	<p>The altSyntax changes the behavior of how tags are interpreted. Instead of evaluating each tag parameter against
	the value stack and needing single quotes to mark string literals, only marked expressions are evaluated.</p>

	<p>Example:</p>

	<p>the following code uses the <a href="tag-syntax.html">Tag Syntax</a>:</p>

	<pre><code class="language-jsp"><s:iterator value="cart.items">
	...
	<s:textfield label="'Cart item No.' + #rowstatus.index + ' note'"
	name="'cart.items[' + #rowstatus.index + '].note'"
	value="note" />
	</s:iterator>
	</code></pre>

	<p>this is somewhat counter intuitive to normal HTML tag behaviour, and you get loads of single quotes. Now the same example
	in altSyntax:</p>

	<pre><code class="language-jsp"><s:iterator value="cart.items">
	...
	<s:textfield label="Cart item No. %{#rowstatus.index} note"
	name="cart.items[%{#rowstatus.index}].note"
	value="%{note}" />
	</s:iterator>
	</code></pre>

	<p>Only expressions enclosed with <code class="highlighter-rouge">%{}</code> are evaluated. The code is shorter and clearer, very similar to JSTL EL usage.
	Quoting problems, eg. with javascript function calls, are avoided.</p>

	<p>In order to fully understand why this option exists and what the differences are, it is best to get a bit of history
	about WebWork.</p>

	<blockquote>
	<p>If you are <em>not</em> upgrading from WebWork 2.1.7 or previous versions and you don’t care about the history of WebWork’s
	evolution, you can skip this section. See the <a href="tag-syntax.html">Tag Syntax</a> section for more information
	on the standard tag syntax support</p>
	</blockquote>

	<h2 id="history">History</h2>

	<p>In WebWork 2.1.4, the altSyntax option was introduced. The book, WebWork in Action, while based around WebWork 2.1.7,
	was entirely written with the assumption that the altSyntax was enabled. As of WebWork 2.2, the altSyntax is turned
	on by default and eventually the old syntax will no longer be supported and will be removed from the code.</p>

	</section>
	</article>


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	Apache Struts, Struts, Apache, the Apache feather logo, and the Apache Struts project logos are
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