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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>Return part 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.substr-replace.html">substr_replace</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.trim.html">trim</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" class="refentry"> <div class="refnamediv"> <h1 class="refname">substr</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">substr</span> — <span class="dc-title">Return part of a string</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">string</span> <span class="methodname"><b><b>substr</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$string</tt></span> , <span class="methodparam"><span class="type">int</span> <tt class="parameter">$start</tt></span> [, <span class="methodparam"><span class="type">int</span> <tt class="parameter">$length</tt></span> ] )</div> <p class="para rdfs-comment"> Returns the portion of <i><tt class="parameter">string</tt></i> specified by the <i><tt class="parameter">start</tt></i> and <i><tt class="parameter">length</tt></i> parameters. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">string</tt></i></span> <dd> <p class="para"> The input string. </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">start</tt></i></span> <dd> <p class="para"> If <i><tt class="parameter">start</tt></i> is non-negative, the returned string will start at the <i><tt class="parameter">start</tt></i>'th position in <i><tt class="parameter">string</tt></i>, counting from zero. For instance, in the string '<i>abcdef</i>', the character at position <i>0</i> is '<i>a</i>', the character at position <i>2</i> is '<i>c</i>', and so forth. </p> <p class="para"> If <i><tt class="parameter">start</tt></i> is negative, the returned string will start at the <i><tt class="parameter">start</tt></i>'th character from the end of <i><tt class="parameter">string</tt></i>. </p> <p class="para"> <div class="example"> <p><b>Example #1 Using a negative <i><tt class="parameter">start</tt></i></b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$rest </span><span style="color: #007700">= </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">"abcdef"</span><span style="color: #007700">, -</span><span style="color: #0000BB">1</span><span style="color: #007700">); </span><span style="color: #FF8000">// returns "f"<br /></span><span style="color: #0000BB">$rest </span><span style="color: #007700">= </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">"abcdef"</span><span style="color: #007700">, -</span><span style="color: #0000BB">2</span><span style="color: #007700">); </span><span style="color: #FF8000">// returns "ef"<br /></span><span style="color: #0000BB">$rest </span><span style="color: #007700">= </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">"abcdef"</span><span style="color: #007700">, -</span><span style="color: #0000BB">3</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">); </span><span style="color: #FF8000">// returns "d"<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">length</tt></i></span> <dd> <p class="para"> If <i><tt class="parameter">length</tt></i> is given and is positive, the string returned will contain at most <i><tt class="parameter">length</tt></i> characters beginning from <i><tt class="parameter">start</tt></i> (depending on the length of <i><tt class="parameter">string</tt></i>). If <i><tt class="parameter">string</tt></i> is less than or equal to <i><tt class="parameter">start</tt></i> characters long, <b><tt>FALSE</tt></b> will be returned. </p> <p class="para"> If <i><tt class="parameter">length</tt></i> is given and is negative, then that many characters will be omitted from the end of <i><tt class="parameter">string</tt></i> (after the start position has been calculated when a <i><tt class="parameter">start</tt></i> is negative). If <i><tt class="parameter">start</tt></i> denotes a position beyond this truncation, an empty string will be returned. </p> <div class="example"> <p><b>Example #2 Using a negative <i><tt class="parameter">length</tt></i></b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />$rest </span><span style="color: #007700">= </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">"abcdef"</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, -</span><span style="color: #0000BB">1</span><span style="color: #007700">); </span><span style="color: #FF8000">// returns "abcde"<br /></span><span style="color: #0000BB">$rest </span><span style="color: #007700">= </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">"abcdef"</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">, -</span><span style="color: #0000BB">1</span><span style="color: #007700">); </span><span style="color: #FF8000">// returns "cde"<br /></span><span style="color: #0000BB">$rest </span><span style="color: #007700">= </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">"abcdef"</span><span style="color: #007700">, </span><span style="color: #0000BB">4</span><span style="color: #007700">, -</span><span style="color: #0000BB">4</span><span style="color: #007700">); </span><span style="color: #FF8000">// returns ""<br /></span><span style="color: #0000BB">$rest </span><span style="color: #007700">= </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">"abcdef"</span><span style="color: #007700">, -</span><span style="color: #0000BB">3</span><span style="color: #007700">, -</span><span style="color: #0000BB">1</span><span style="color: #007700">); </span><span style="color: #FF8000">// returns "de"<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns the extracted part of string. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #3 Basic <b>substr()</b> usage</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">'abcdef'</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">); </span><span style="color: #FF8000">// bcdef<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">'abcdef'</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">); </span><span style="color: #FF8000">// bcd<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">'abcdef'</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">4</span><span style="color: #007700">); </span><span style="color: #FF8000">// abcd<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">'abcdef'</span><span style="color: #007700">, </span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">8</span><span style="color: #007700">); </span><span style="color: #FF8000">// abcdef<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">substr</span><span style="color: #007700">(</span><span style="color: #DD0000">'abcdef'</span><span style="color: #007700">, -</span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">); </span><span style="color: #FF8000">// f<br /><br />// Accessing single characters in a string<br />// can also be achieved using "square brackets"<br /></span><span style="color: #0000BB">$string </span><span style="color: #007700">= </span><span style="color: #DD0000">'abcdef'</span><span style="color: #007700">;<br />echo </span><span style="color: #0000BB">$string</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">]; </span><span style="color: #FF8000">// a<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">$string</span><span style="color: #007700">[</span><span style="color: #0000BB">3</span><span style="color: #007700">]; </span><span style="color: #FF8000">// d<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">$string</span><span style="color: #007700">[</span><span style="color: #0000BB">strlen</span><span style="color: #007700">(</span><span style="color: #0000BB">$string</span><span style="color: #007700">)-</span><span style="color: #0000BB">1</span><span style="color: #007700">]; </span><span style="color: #FF8000">// f<br /><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.strrchr.html" class="function" rel="rdfs-seeAlso">strrchr()</a></li> <li class="member"><a href="function.substr-replace.html" class="function" rel="rdfs-seeAlso">substr_replace()</a></li> <li class="member"><a href="function.preg-match.html" class="function" rel="rdfs-seeAlso">preg_match()</a></li> <li class="member"><a href="function.trim.html" class="function" rel="rdfs-seeAlso">trim()</a></li> <li class="member"><a href="function.mb-substr.html" class="function" rel="rdfs-seeAlso">mb_substr()</a></li> <li class="member"><a href="function.wordwrap.html" class="function" rel="rdfs-seeAlso">wordwrap()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; 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