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<title>Searches the array for a given value and returns the corresponding key if successful</title>
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<h1 class="refname">array_search</h1>
<p class="verinfo">(PHP 4 >= 4.0.5, PHP 5)</p><p class="refpurpose"><span class="refname">array_search</span> — <span class="dc-title">Searches the array for a given value and returns the corresponding key if successful</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.array-search-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <span class="methodname"><strong>array_search</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">$needle</code></span>
, <span class="methodparam"><span class="type">array</span> <code class="parameter">$haystack</code></span>
[, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$strict</code><span class="initializer"> = false</span></span>
] )</div>
<p class="para rdfs-comment">
Searches <em><code class="parameter">haystack</code></em> for <em><code class="parameter">needle</code></em>.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.array-search-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">needle</code></em></span>
<dd>
<p class="para">
The searched value.
</p>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
If <em><code class="parameter">needle</code></em> is a string, the comparison is done
in a case-sensitive manner.
</p>
</p></blockquote>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">haystack</code></em></span>
<dd>
<p class="para">
The array.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">strict</code></em></span>
<dd>
<p class="para">
If the third parameter <em><code class="parameter">strict</code></em> is set to <strong><code>TRUE</code></strong>
then the <span class="function"><strong>array_search()</strong></span> function will search for
<em class="emphasis">identical</em> elements in the
<em><code class="parameter">haystack</code></em>. This means it will also check the
<a href="language.types.html" class="link">types</a> of the
<em><code class="parameter">needle</code></em> in the <em><code class="parameter">haystack</code></em>,
and objects must be the same instance.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.array-search-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns the key for <em><code class="parameter">needle</code></em> if it is found in the
array, <strong><code>FALSE</code></strong> otherwise.
</p>
<p class="para">
If <em><code class="parameter">needle</code></em> is found in <em><code class="parameter">haystack</code></em>
more than once, the first matching key is returned. To return the keys for
all matching values, use <span class="function"><a href="function.array-keys.html" class="function">array_keys()</a></span> with the optional
<em><code class="parameter">search_value</code></em> parameter instead.
</p>
<div class="warning"><strong class="warning">Warning</strong><p class="simpara">This function may
return Boolean <strong><code>FALSE</code></strong>, but may also return a non-Boolean value which
evaluates to <strong><code>FALSE</code></strong>. Please read the section on <a href="language.types.boolean.html" class="link">Booleans</a> for more
information. Use <a href="language.operators.comparison.html" class="link">the ===
operator</a> for testing the return value of this
function.</p></div>
</div>
<div class="refsect1 changelog" id="refsect1-function.array-search-changelog">
<h3 class="title">Changelog</h3>
<p class="para">
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>5.3.0</td>
<td>
As with all internal PHP functions as of 5.3.0,
<span class="function"><strong>array_search()</strong></span> returns <strong><code>NULL</code></strong> if invalid parameters
are passed to it.
</td>
</tr>
<tr>
<td>4.2.0</td>
<td>
Prior to PHP 4.2.0, <span class="function"><strong>array_search()</strong></span> returns <strong><code>NULL</code></strong>
on failure instead of <strong><code>FALSE</code></strong>.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.array-search-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-4980">
<p><strong>Example #1 <span class="function"><strong>array_search()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$array </span><span style="color: #007700">= array(</span><span style="color: #0000BB">0 </span><span style="color: #007700">=> </span><span style="color: #DD0000">'blue'</span><span style="color: #007700">, </span><span style="color: #0000BB">1 </span><span style="color: #007700">=> </span><span style="color: #DD0000">'red'</span><span style="color: #007700">, </span><span style="color: #0000BB">2 </span><span style="color: #007700">=> </span><span style="color: #DD0000">'green'</span><span style="color: #007700">, </span><span style="color: #0000BB">3 </span><span style="color: #007700">=> </span><span style="color: #DD0000">'red'</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$key </span><span style="color: #007700">= </span><span style="color: #0000BB">array_search</span><span style="color: #007700">(</span><span style="color: #DD0000">'green'</span><span style="color: #007700">, </span><span style="color: #0000BB">$array</span><span style="color: #007700">); </span><span style="color: #FF8000">// $key = 2;<br /></span><span style="color: #0000BB">$key </span><span style="color: #007700">= </span><span style="color: #0000BB">array_search</span><span style="color: #007700">(</span><span style="color: #DD0000">'red'</span><span style="color: #007700">, </span><span style="color: #0000BB">$array</span><span style="color: #007700">); </span><span style="color: #FF8000">// $key = 1;<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.array-search-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.array-keys.html" class="function" rel="rdfs-seeAlso">array_keys()</a> - Return all the keys or a subset of the keys of an array</span></li>
<li class="member"> <span class="function"><a href="function.array-values.html" class="function" rel="rdfs-seeAlso">array_values()</a> - Return all the values of an array</span></li>
<li class="member"> <span class="function"><a href="function.array-key-exists.html" class="function" rel="rdfs-seeAlso">array_key_exists()</a> - Checks if the given key or index exists in the array</span></li>
<li class="member"> <span class="function"><a href="function.in-array.html" class="function" rel="rdfs-seeAlso">in_array()</a> - Checks if a value exists in an array</span></li>
</ul>
</p>
</div>
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