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<title>Dumps information about a variable</title>
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<div class="refnamediv">
<h1 class="refname">var_dump</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">var_dump</span> — <span class="dc-title">Dumps information about a variable</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.var-dump-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type"><span class="type void">void</span></span> <span class="methodname"><strong>var_dump</strong></span>
( <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$expression</code></span>
[, <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$...</code></span>
] )</div>
<p class="simpara">
This function displays structured information about one or more
expressions that includes its type and value. Arrays and objects are
explored recursively with values indented to show structure.
</p>
<p class="simpara">
In PHP 5 all public, private and protected properties of objects will be
returned in the output.
</p>
<div class="tip"><strong class="tip">Tip</strong><p class="simpara">As with anything that outputs
its result directly to the browser, the <a href="book.outcontrol.html" class="link">output-control functions</a> can be used to capture
the output of this function, and save it in a
<span class="type"><a href="language.types.string.html" class="type string">string</a></span> (for example).</p></div>
</div>
<div class="refsect1 parameters" id="refsect1-function.var-dump-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">expression</code></em></span>
<dd>
<p class="para">
The variable you want to dump.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.var-dump-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
No value is returned.
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.var-dump-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-5278">
<p><strong>Example #1 <span class="function"><strong>var_dump()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$a </span><span style="color: #007700">= array(</span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">, array(</span><span style="color: #DD0000">"a"</span><span style="color: #007700">, </span><span style="color: #DD0000">"b"</span><span style="color: #007700">, </span><span style="color: #DD0000">"c"</span><span style="color: #007700">));<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$a</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
array(3) {
[0]=>
int(1)
[1]=>
int(2)
[2]=>
array(3) {
[0]=>
string(1) "a"
[1]=>
string(1) "b"
[2]=>
string(1) "c"
}
}
</pre></div>
</div>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br />$b </span><span style="color: #007700">= </span><span style="color: #0000BB">3.1</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$c </span><span style="color: #007700">= </span><span style="color: #0000BB">true</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$b</span><span style="color: #007700">, </span><span style="color: #0000BB">$c</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
float(3.1)
bool(true)
</pre></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.var-dump-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.print-r.html" class="function" rel="rdfs-seeAlso">print_r()</a> - Prints human-readable information about a variable</span></li>
<li class="member"> <span class="function"><a href="function.debug-zval-dump.html" class="function" rel="rdfs-seeAlso">debug_zval_dump()</a> - Dumps a string representation of an internal zend value to output</span></li>
<li class="member"> <span class="function"><a href="function.var-export.html" class="function" rel="rdfs-seeAlso">var_export()</a> - Outputs or returns a parsable string representation of a variable</span></li>
</ul>
</p>
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