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<img alt="->" src="../images/arrow.gif" /> <if></td>
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v0.91</td>
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<h1><if></h1>
<p> Checks the conditional attributes and executes the children if <b>true</b>. </p>
<p> If no conditions are checked, all child tasks are executed. </p>
<p> If more than one attribute is used, they are &&'d. The first to fail stops the check. </p>
<p> The order of condition evaluation is, <code>targetexists</code>, <code>propertyexists</code>, <code>propertytrue</code>, <code>uptodatefile</code>. </p>
<p class="i2">
<b>Note:</b> instead of using the deprecated attributes, we advise you to use the following functions in combination with the <code>test</code> attribute: </p>
<div class="table">
<table>
<tr>
<th>Function</th>
<th>Description</th>
</tr>
<tr>
<td>
<a href="../functions/property.exists(System.String).html">property::exists()</a>
</td>
<td>Checks whether the specified property exists.</td>
</tr>
<tr>
<td>
<a href="../functions/target.exists(System.String).html">target::exists()</a>
</td>
<td>Checks whether the specified target exists.</td>
</tr>
</table>
</div>
<h3>Parameters</h3>
<div class="table">
<table>
<tr>
<th>Attribute</th>
<th style="text-align: center;">Type</th>
<th>Description</th>
<th style="text-align: center;">Required</th>
</tr>
<tr>
<td valign="top">comparefile</td>
<td style="text-align: center;">string</td>
<td>
<i>Deprecated.</i> The file to check against for the uptodate file. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">propertyexists</td>
<td style="text-align: center;">string</td>
<td>
<i>Deprecated.</i> Used to test whether a property exists. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">propertytrue</td>
<td style="text-align: center;">string</td>
<td>
<i>Deprecated.</i> Used to test whether a property is true. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">targetexists</td>
<td style="text-align: center;">string</td>
<td>
<i>Deprecated.</i> Used to test whether a target exists. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">test</td>
<td style="text-align: center;">string</td>
<td> Used to test arbitrary boolean expression. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">uptodatefile</td>
<td style="text-align: center;">string</td>
<td>
<i>Deprecated.</i> The file to compare if uptodate. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">failonerror</td>
<td style="text-align: center;">bool</td>
<td> Determines if task failure stops the build, or is just reported. The default is <b>true</b>. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">if</td>
<td style="text-align: center;">bool</td>
<td> If <b>true</b> then the task will be executed; otherwise, skipped. The default is <b>true</b>. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">unless</td>
<td style="text-align: center;">bool</td>
<td> Opposite of <code>if</code>. If <b>false</b> then the task will be executed; otherwise, skipped. The default is <b>false</b>. </td>
<td style="text-align: center;">False</td>
</tr>
<tr>
<td valign="top">verbose</td>
<td style="text-align: center;">bool</td>
<td> Determines whether the task should report detailed build log messages. The default is <b>false</b>. </td>
<td style="text-align: center;">False</td>
</tr>
</table>
</div>
<h3>Nested Elements:</h3>
<!--Element-->
<h4>
<a id="comparefiles">
</a>
<<a href="../types/fileset.html">comparefiles</a>>
</h4>
<div class="nested-element">
<i>Deprecated.</i> The <a href="../types/fileset.html"><fileset></a> that contains the comparison files for the <code>uptodatefile</code>(s) check. <p /></div>
<h4>
<a id="comparefiles">
</a>
</<a href="../types/fileset.html">comparefiles</a>>
</h4>
<!--Element-->
<h4>
<a id="uptodatefiles">
</a>
<<a href="../types/fileset.html">uptodatefiles</a>>
</h4>
<div class="nested-element">
<i>Deprecated.</i> The <a href="../types/fileset.html"><fileset></a> that contains the uptodate files for the <code>comparefile</code>(s) check. <p /></div>
<h4>
<a id="uptodatefiles">
</a>
</<a href="../types/fileset.html">uptodatefiles</a>>
</h4>
<h3>Examples</h3>
<ul class="examples">
<li>
<p>Tests the value of a property using expressions.</p>
<pre class="code">
<if test="${build.configuration=='release'}">
<echo>Build release configuration</echo>
</if>
</pre>
</li>
<li>
<p>Tests the the output of a function.</p>
<pre class="code">
<if test="${not file::exists(filename) or file::get-length(filename) = 0}">
<echo message="The version file ${filename} doesn't exist or is empty!" />
</if>
</pre>
</li>
<li>
<p>
<code>(Deprecated)</code> Check that a target exists.</p>
<pre class="code">
<target name="myTarget" />
<if targetexists="myTarget">
<echo message="myTarget exists" />
</if>
</pre>
</li>
<li>
<p>
<code>(Deprecated)</code> Check existence of a property.</p>
<pre class="code">
<if propertyexists="myProp">
<echo message="myProp Exists. Value='${myProp}'" />
</if>
</pre>
</li>
<li>
<p>
<code>(Deprecated)</code> Check that a property value is true.</p>
<pre class="code">
<if propertytrue="myProp">
<echo message="myProp is true. Value='${myProp}'" />
</if>
</pre>
</li>
<li>
<p>
<code>(Deprecated)</code> Check that a property exists and is <b>true</b> (uses multiple conditions). </p>
<pre class="code">
<if propertyexists="myProp" propertytrue="myProp">
<echo message="myProp is '${myProp}'" />
</if>
</pre>
<p>which is the same as</p>
<pre class="code">
<if propertyexists="myProp">
<if propertytrue="myProp">
<echo message="myProp is '${myProp}'" />
</if>
</if>
</pre>
</li>
<li>
<p>
<code>(Deprecated)</code> Check file dates. If <code>myfile.dll</code> is uptodate, then do stuff. </p>
<pre class="code">
<if uptodatefile="myfile.dll" comparefile="myfile.cs">
<echo message="myfile.dll is newer/same-date as myfile.cs" />
</if>
</pre>
<p>or</p>
<pre class="code">
<if uptodatefile="myfile.dll">
<comparefiles>
<include name="*.cs" />
</comparefiles>
<echo message="myfile.dll is newer/same-date as myfile.cs" />
</if>
</pre>
<p>or</p>
<pre class="code">
<if>
<uptodatefiles>
<include name="myfile.dll" />
</uptodatefiles>
<comparefiles>
<include name="*.cs" />
</comparefiles>
<echo message="myfile.dll is newer/same-date as myfile.cs" />
</if>
</pre>
</li>
</ul>
<h3>Requirements</h3>
<div style="margin-left: 20px;">
<b>Assembly:</b> NAnt.Core (0.91.4312.0)
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