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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>Get the integer value of a variable</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.import-request-variables.html">import_request_variables</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.is-array.html">is_array</a></div> <div class="up"><a href="ref.var.html">Variable handling Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.intval" class="refentry"> <div class="refnamediv"> <h1 class="refname">intval</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">intval</span> — <span class="dc-title">Get the integer value of a variable</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>intval</b></b></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">$var</tt></span> [, <span class="methodparam"><span class="type">int</span> <tt class="parameter">$base</tt></span> ] )</div> <p class="para rdfs-comment"> Returns the <a href="language.types.integer.html" class="type integer">integer</a> value of <i><tt class="parameter">var</tt></i>, using the specified <i><tt class="parameter">base</tt></i> for the conversion (the default is base 10). </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">var</tt></i></span> <dd> <p class="para"> The scalar value being converted to an integer </p> </dd> </dt> <dt> <span class="term"><i><tt class="parameter">base</tt></i></span> <dd> <p class="para"> The base for the conversion (default is base 10) </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> The integer value of <i><tt class="parameter">var</tt></i> on success, or 0 on failure. Empty arrays and objects return 0, non-empty arrays and objects return 1. </p> <p class="para"> The maximum value depends on the system. 32 bit systems have a maximum signed integer range of -2147483648 to 2147483647. So for example on such a system, <i>intval('1000000000000')</i> will return 2147483647. The maximum signed integer value for 64 bit systems is 9223372036854775807. </p> <p class="para"> Strings will most likely return 0 although this depends on the leftmost characters of the string. The common rules of <a href="language.types.integer.html#language.types.integer.casting" class="link">integer casting</a> apply. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 <b>intval()</b> examples</b></p> <div class="example-contents"><p> The following examples are based on a 32 bit system. </p></div> <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">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">42</span><span style="color: #007700">); </span><span style="color: #FF8000">// 42<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">4.2</span><span style="color: #007700">); </span><span style="color: #FF8000">// 4<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #DD0000">'42'</span><span style="color: #007700">); </span><span style="color: #FF8000">// 42<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #DD0000">'+42'</span><span style="color: #007700">); </span><span style="color: #FF8000">// 42<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #DD0000">'-42'</span><span style="color: #007700">); </span><span style="color: #FF8000">// -42<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">042</span><span style="color: #007700">); </span><span style="color: #FF8000">// 34<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #DD0000">'042'</span><span style="color: #007700">); </span><span style="color: #FF8000">// 42<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">1e10</span><span style="color: #007700">); </span><span style="color: #FF8000">// 1410065408<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #DD0000">'1e10'</span><span style="color: #007700">); </span><span style="color: #FF8000">// 1<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">0x1A</span><span style="color: #007700">); </span><span style="color: #FF8000">// 26<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">42000000</span><span style="color: #007700">); </span><span style="color: #FF8000">// 42000000<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">420000000000000000000</span><span style="color: #007700">); </span><span style="color: #FF8000">// 0<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #DD0000">'420000000000000000000'</span><span style="color: #007700">); </span><span style="color: #FF8000">// 2147483647<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #0000BB">42</span><span style="color: #007700">, </span><span style="color: #0000BB">8</span><span style="color: #007700">); </span><span style="color: #FF8000">// 42<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">intval</span><span style="color: #007700">(</span><span style="color: #DD0000">'42'</span><span style="color: #007700">, </span><span style="color: #0000BB">8</span><span style="color: #007700">); </span><span style="color: #FF8000">// 34<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </div> <div class="refsect1 notes"> <h3 class="title">Notes</h3> <blockquote><p><b class="note">Note</b>: The <i><tt class="parameter">base</tt></i> parameter has no effect unless the <i><tt class="parameter">var</tt></i> parameter is a string. <br /> </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.floatval.html" class="function" rel="rdfs-seeAlso">floatval()</a></li> <li class="member"><a href="function.strval.html" class="function" rel="rdfs-seeAlso">strval()</a></li> <li class="member"><a href="function.settype.html" class="function" rel="rdfs-seeAlso">settype()</a></li> <li class="member"><a href="function.is-numeric.html" class="function" rel="rdfs-seeAlso">is_numeric()</a></li> <li class="member"><a href="language.types.type-juggling.html" class="link">Type juggling</a></li> <li class="member"><a href="ref.bc.html" class="link">BCMath Arbitrary Precision Mathematics Functions</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; 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