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Zenon Page Templates - JS (ZPT-JS)

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<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <title>Conditionals</title> <script type="module" src="../js/zpt.js"></script> <script type="text/javascript" src="../lib/syntaxHighlighter/lib.js"></script> <link rel="stylesheet" type="text/css" href="../docs.css"> <link rel="stylesheet" type="text/css" href="../lib/syntaxHighlighter/theme.css"> </head> <body> <div data-use-macro="'page@templates.html'"> <div data-fill-slot="'page-header'"> <h1>ZPT-JS tutorial - Conditionals</h1> <ul> <li><a href="#simple">Simple conditionals</a>.</li> </ul> </div> <article data-fill-slot="'article'"> <h2 data-attributes="id 'simple'">Simple conditionals</h2> <p> Sometimes we want to show some HTML elements depending on a condition. This can be done using <em>data-condition</em> attribute. Using it the element and its content will be shown only if the condition is evaluated to <code>true</code>. Let's see an example: </p> <strong>sample.html</strong> <pre class="brush: html"> &lt;p data-condition="user/isLogged()"&gt; Logged users stuff ... &lt;/p&gt; </pre> <p> ZPT-JS evaluates the <em>user/isLogged()</em> expression: only if it evaluated to <code>true</code> the <em>p</em> tag will be parsed and shown. Otherwise it will not be parsed but hidden. </p> <p> But... when does an expression evaluate to <code>true</code>? If an expression evaluates to any of the next: </p> <ul> <li><code>undefined</code></li> <li><code>null</code></li> <li><code>'false'</code></li> <li><code>false</code></li> <li><code>0</code></li> </ul> <p> the expression evaluates to <code>false</code>. Otherwise the expression evaluates to <code>true</code>. </p> </article> </div> </body> </html>