📄 function.substr-count.html
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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>Count the number of substring occurrences</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.substr-compare.html">substr_compare</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.substr-replace.html">substr_replace</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.substr-count" class="refentry"> <div class="refnamediv"> <h1 class="refname">substr_count</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">substr_count</span> — <span class="dc-title">Count the number of substring occurrences</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>substr_count</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$haystack</tt></span> , <span class="methodparam"><span class="type">string</span> <tt class="parameter">$needle</tt></span> [, <span class="methodparam"><span class="type">int</span> <tt class="parameter">$offset</tt></span> [, <span class="methodparam"><span class="type">int</span> <tt class="parameter">$length</tt></span> ]] )</div> <p class="para rdfs-comment"> <b>substr_count()</b> returns the number of times the <i><tt class="parameter">needle</tt></i> substring occurs in the <i><tt class="parameter">haystack</tt></i> string. Please note that <i><tt class="parameter">needle</tt></i> is case sensitive. </p> <blockquote><p><b class="note">Note</b>: This function doesn't count overlapped substrings. See the example below! <br /> </p></blockquote> </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"> The substring to search for </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">offset</tt></i></span> <dd> <p class="para"> The offset where to start counting </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">length</tt></i></span> <dd> <p class="para"> The maximum length after the specified offset to search for the substring. It outputs a warning if the offset plus the length is greater than the <i><tt class="parameter">haystack</tt></i> length. </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> This functions returns an <a href="language.types.integer.html" class="type integer">integer</a>. </p> </div> <div class="refsect1 changelog"> <h3 class="title">ChangeLog</h3> <p class="para"> <table class="informaltable"> <colgroup> <thead valign="middle"> <tr valign="middle"> <th colspan="1">Version</th> <th colspan="1">Description</th> </tr> </thead> <tbody valign="middle" class="tbody"> <tr valign="middle"> <td colspan="1" rowspan="1" align="left">5.1.0</td> <td colspan="1" rowspan="1" align="left"> Added the <i><tt class="parameter">offset</tt></i> and the <i><tt class="parameter">length</tt></i> parameters </td> </tr> </tbody> </colgroup> </table> </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 A <b>substr_count()</b> example</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$text </span><span style="color: #007700">= </span><span style="color: #DD0000">'This is a test'</span><span style="color: #007700">;<br />echo </span><span style="color: #0000BB">strlen</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">); </span><span style="color: #FF8000">// 14<br /><br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">, </span><span style="color: #DD0000">'is'</span><span style="color: #007700">); </span><span style="color: #FF8000">// 2<br /><br />// the string is reduced to 's is a test', so it prints 1<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">, </span><span style="color: #DD0000">'is'</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// the text is reduced to 's i', so it prints 0<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">, </span><span style="color: #DD0000">'is'</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// generates a warning because 5+10 > 14<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$text</span><span style="color: #007700">, </span><span style="color: #DD0000">'is'</span><span style="color: #007700">, </span><span style="color: #0000BB">5</span><span style="color: #007700">, </span><span style="color: #0000BB">10</span><span style="color: #007700">);<br /><br /><br /></span><span style="color: #FF8000">// prints only 1, because it doesn't count overlapped subtrings<br /></span><span style="color: #0000BB">$text2 </span><span style="color: #007700">= </span><span style="color: #DD0000">'gcdgcdgcd'</span><span style="color: #007700">;<br />echo </span><span style="color: #0000BB">substr_count</span><span style="color: #007700">(</span><span style="color: #0000BB">$text2</span><span style="color: #007700">, </span><span style="color: #DD0000">'gcdgcd'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.count-chars.html" class="function" rel="rdfs-seeAlso">count_chars()</a></li> <li class="member"><a href="function.strpos.html" class="function" rel="rdfs-seeAlso">strpos()</a></li> <li class="member"><a href="function.substr.html" class="function" rel="rdfs-seeAlso">substr()</a></li> <li class="member"><a href="function.strstr.html" class="function" rel="rdfs-seeAlso">strstr()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; 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