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<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head>  <title>Find position of first occurrence of a string</title>  <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.strpbrk.html">strpbrk</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.strrchr.html">strrchr</a></div> <div class="up"><a href="ref.strings.html">String Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.strpos" class="refentry"> <div class="refnamediv">  <h1 class="refname">strpos</h1>  <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">strpos</span> &mdash; <span class="dc-title">Find position of first occurrence of a string</span></p> </div>  <div class="refsect1 description">  <h3 class="title">Description</h3>  <div class="methodsynopsis dc-description">   <span class="type">int</span> <span class="methodname"><b><b>strpos</b></b></span>    ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$haystack</tt></span>   , <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <tt class="parameter">$needle</tt></span>   [, <span class="methodparam"><span class="type">int</span> <tt class="parameter">$offset</tt></span>  ] )</div>  <p class="para rdfs-comment">   Returns the numeric position of the first occurrence of   <i><tt class="parameter">needle</tt></i> in the <i><tt class="parameter">haystack</tt></i>   string.  Unlike the <a href="function.strrpos.html" class="function">strrpos()</a> before PHP 5, this   function can take a full string as the <i><tt class="parameter">needle</tt></i>   parameter and the entire string will be used.  </p> </div> <div class="refsect1 parameters">  <h3 class="title">Parameters</h3>  <p class="para">   <dl>    <dt>     <span class="term"><i><tt class="parameter">haystack</tt></i></span>     <dd>      <p class="para">       The string to search in      </p>     </dd>    </dt>    <dt>     <span class="term"><i><tt class="parameter">needle</tt></i></span>     <dd>      <p class="para">       If <i><tt class="parameter">needle</tt></i> is not a string, it is converted       to an integer and applied as the ordinal value of a character.      </p>     </dd>    </dt>    <dt>     <span class="term"><i><tt class="parameter">offset</tt></i></span>     <dd>      <p class="para">       The optional <i><tt class="parameter">offset</tt></i> parameter allows you       to specify which character in <i><tt class="parameter">haystack</tt></i> to       start searching. The position returned is still relative to the       beginning of <i><tt class="parameter">haystack</tt></i>.      </p>     </dd>    </dt>   </dl>  </p> </div> <div class="refsect1 returnvalues">  <h3 class="title">Return Values</h3>  <p class="para">   Returns the position as an integer. If <i><tt class="parameter">needle</tt></i> is   not found, <b>strpos()</b> will return <a href="language.types.boolean.html" class="type boolean">boolean</a>   <b><tt>FALSE</tt></b>.  </p>  <div class="warning"><b class="warning">Warning</b><p class="simpara">This function mayreturn Boolean <b><tt>FALSE</tt></b>, but may also return a non-Boolean value whichevaluates to <b><tt>FALSE</tt></b>, such as <i>0</i> or&quot;&quot;. Please read the section on <a href="language.types.boolean.html" class="link">Booleans</a> for moreinformation. Use <a href="language.operators.comparison.html" class="link">the ===operator</a> for testing the return value of thisfunction.</p></div> </div> <div class="refsect1 examples">  <h3 class="title">Examples</h3>  <p class="para">   <div class="example">    <p><b>Example #1 Using ===</b></p>    <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br />$mystring&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">'abc'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$findme&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">'a'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$pos&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">strpos</span><span style="color: #007700">(</span><span style="color: #0000BB">$mystring</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$findme</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">//&nbsp;Note&nbsp;our&nbsp;use&nbsp;of&nbsp;===.&nbsp;&nbsp;Simply&nbsp;==&nbsp;would&nbsp;not&nbsp;work&nbsp;as&nbsp;expected<br />//&nbsp;because&nbsp;the&nbsp;position&nbsp;of&nbsp;'a'&nbsp;was&nbsp;the&nbsp;0th&nbsp;(first)&nbsp;character.<br /></span><span style="color: #007700">if&nbsp;(</span><span style="color: #0000BB">$pos&nbsp;</span><span style="color: #007700">===&nbsp;</span><span style="color: #0000BB">false</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"The&nbsp;string&nbsp;'$findme'&nbsp;was&nbsp;not&nbsp;found&nbsp;in&nbsp;the&nbsp;string&nbsp;'$mystring'"</span><span style="color: #007700">;<br />}&nbsp;else&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"The&nbsp;string&nbsp;'$findme'&nbsp;was&nbsp;found&nbsp;in&nbsp;the&nbsp;string&nbsp;'$mystring'"</span><span style="color: #007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"&nbsp;and&nbsp;exists&nbsp;at&nbsp;position&nbsp;$pos"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?&gt;</span></span></code></div>    </div>   </div>   <div class="example">    <p><b>Example #2 Using !==</b></p>    <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br />$mystring&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">'abc'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$findme&nbsp;&nbsp;&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">'a'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$pos&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">strpos</span><span style="color: #007700">(</span><span style="color: #0000BB">$mystring</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$findme</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">//&nbsp;The&nbsp;!==&nbsp;operator&nbsp;can&nbsp;also&nbsp;be&nbsp;used.&nbsp;&nbsp;Using&nbsp;!=&nbsp;would&nbsp;not&nbsp;work&nbsp;as&nbsp;expected<br />//&nbsp;because&nbsp;the&nbsp;position&nbsp;of&nbsp;'a'&nbsp;is&nbsp;0.&nbsp;The&nbsp;statement&nbsp;(0&nbsp;!=&nbsp;false)&nbsp;evaluates&nbsp;<br />//&nbsp;to&nbsp;false.<br /></span><span style="color: #007700">if&nbsp;(</span><span style="color: #0000BB">$pos&nbsp;</span><span style="color: #007700">!==&nbsp;</span><span style="color: #0000BB">false</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"The&nbsp;string&nbsp;'$findme'&nbsp;was&nbsp;found&nbsp;in&nbsp;the&nbsp;string&nbsp;'$mystring'"</span><span style="color: #007700">;<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"&nbsp;and&nbsp;exists&nbsp;at&nbsp;position&nbsp;$pos"</span><span style="color: #007700">;<br />}&nbsp;else&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"The&nbsp;string&nbsp;'$findme'&nbsp;was&nbsp;not&nbsp;found&nbsp;in&nbsp;the&nbsp;string&nbsp;'$mystring'"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?&gt;</span></span></code></div>    </div>   </div>   <div class="example">    <p><b>Example #3 Using an offset</b></p>    <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br /></span><span style="color: #FF8000">//&nbsp;We&nbsp;can&nbsp;search&nbsp;for&nbsp;the&nbsp;character,&nbsp;ignoring&nbsp;anything&nbsp;before&nbsp;the&nbsp;offset<br /></span><span style="color: #0000BB">$newstring&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #DD0000">'abcdef&nbsp;abcdef'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$pos&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">strpos</span><span style="color: #007700">(</span><span style="color: #0000BB">$newstring</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'a'</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">);&nbsp;</span><span style="color: #FF8000">//&nbsp;$pos&nbsp;=&nbsp;7,&nbsp;not&nbsp;0<br /></span><span style="color: #0000BB">?&gt;</span></span></code></div>    </div>   </div>  </p> </div> <div class="refsect1 notes">  <h3 class="title">Notes</h3>  <blockquote><p><b class="note">Note</b>: <span class="simpara">This function isbinary-safe.</span></p></blockquote> </div> <div class="refsect1 seealso">  <h3 class="title">See Also</h3>  <p class="para">   <ul class="simplelist">    <li class="member"><a href="function.strrpos.html" class="function" rel="rdfs-seeAlso">strrpos()</a></li>    <li class="member"><a href="function.stripos.html" class="function" rel="rdfs-seeAlso">stripos()</a></li>    <li class="member"><a href="function.strripos.html" class="function" rel="rdfs-seeAlso">strripos()</a></li>    <li class="member"><a href="function.strrchr.html" class="function" rel="rdfs-seeAlso">strrchr()</a></li>    <li class="member"><a href="function.substr.html" class="function" rel="rdfs-seeAlso">substr()</a></li>    <li class="member"><a href="function.stristr.html" class="function" rel="rdfs-seeAlso">stristr()</a></li>    <li class="member"><a href="function.strstr.html" class="function" rel="rdfs-seeAlso">strstr()</a></li>   </ul>  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