<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>Check for numeric character(s)</title>
</head>
<body><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="function.ctype-cntrl.html">ctype_cntrl</a></div>
<div class="next" style="text-align: right; float: right;"><a href="function.ctype-graph.html">ctype_graph</a></div>
<div class="up"><a href="ref.ctype.html">Ctype Functions</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div><hr /><div id="function.ctype-digit" class="refentry">
<div class="refnamediv">
<h1 class="refname">ctype_digit</h1>
<p class="verinfo">(PHP 4 >= 4.0.4, PHP 5)</p><p class="refpurpose"><span class="refname">ctype_digit</span> — <span class="dc-title">Check for numeric character(s)</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.ctype-digit-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">bool</span> <span class="methodname"><strong>ctype_digit</strong></span>
( <span class="methodparam"><span class="type">string</span> <code class="parameter">$text</code></span>
)</div>
<p class="para rdfs-comment">
Checks if all of the characters in the provided <span class="type"><a href="language.types.string.html" class="type string">string</a></span>,
<em><code class="parameter">text</code></em>, are numerical.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.ctype-digit-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">text</code></em></span>
<dd>
<p class="para">
The tested string.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.ctype-digit-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns <strong><code>TRUE</code></strong> if every character in the string
<em><code class="parameter">text</code></em> is a decimal digit, <strong><code>FALSE</code></strong> otherwise.
</p>
</div>
<div class="refsect1 changelog" id="refsect1-function.ctype-digit-changelog">
<h3 class="title">Changelog</h3>
<p class="para">
<table class="doctable informaltable">
<thead>
<tr>
<th>Version</th>
<th>Description</th>
</tr>
</thead>
<tbody class="tbody">
<tr>
<td>5.1.0</td>
<td>
Before PHP 5.1.0, this function returned <strong><code>TRUE</code></strong>
when <em><code class="parameter">text</code></em> was an empty string.
</td>
</tr>
</tbody>
</table>
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.ctype-digit-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-5074">
<p><strong>Example #1 A <span class="function"><strong>ctype_digit()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$strings </span><span style="color: #007700">= array(</span><span style="color: #DD0000">'1820.20'</span><span style="color: #007700">, </span><span style="color: #DD0000">'10002'</span><span style="color: #007700">, </span><span style="color: #DD0000">'wsl!12'</span><span style="color: #007700">);<br />foreach (</span><span style="color: #0000BB">$strings </span><span style="color: #007700">as </span><span style="color: #0000BB">$testcase</span><span style="color: #007700">) {<br /> if (</span><span style="color: #0000BB">ctype_digit</span><span style="color: #007700">(</span><span style="color: #0000BB">$testcase</span><span style="color: #007700">)) {<br /> echo </span><span style="color: #DD0000">"The string </span><span style="color: #0000BB">$testcase</span><span style="color: #DD0000"> consists of all digits.\n"</span><span style="color: #007700">;<br /> } else {<br /> echo </span><span style="color: #DD0000">"The string </span><span style="color: #0000BB">$testcase</span><span style="color: #DD0000"> does not consist of all digits.\n"</span><span style="color: #007700">;<br /> }<br />}<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
The string 1820.20 does not consist of all digits.
The string 10002 consists of all digits.
The string wsl!12 does not consist of all digits.
</pre></div>
</div>
</div>
</p>
<p class="para">
<div class="example" id="example-5075">
<p><strong>Example #2 A <span class="function"><strong>ctype_digit()</strong></span> example comparing strings with integers</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /><br />$numeric_string </span><span style="color: #007700">= </span><span style="color: #DD0000">'42'</span><span style="color: #007700">;<br /></span><span style="color: #0000BB">$integer </span><span style="color: #007700">= </span><span style="color: #0000BB">42</span><span style="color: #007700">;<br /><br /></span><span style="color: #0000BB">ctype_digit</span><span style="color: #007700">(</span><span style="color: #0000BB">$numeric_string</span><span style="color: #007700">); </span><span style="color: #FF8000">// true<br /></span><span style="color: #0000BB">ctype_digit</span><span style="color: #007700">(</span><span style="color: #0000BB">$integer</span><span style="color: #007700">); </span><span style="color: #FF8000">// false (ASCII 42 is the * character)<br /><br /></span><span style="color: #0000BB">is_numeric</span><span style="color: #007700">(</span><span style="color: #0000BB">$numeric_string</span><span style="color: #007700">); </span><span style="color: #FF8000">// true<br /></span><span style="color: #0000BB">is_numeric</span><span style="color: #007700">(</span><span style="color: #0000BB">$integer</span><span style="color: #007700">); </span><span style="color: #FF8000">// true<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
</div>
</p>
</div>
<div class="refsect1 notes" id="refsect1-function.ctype-digit-notes">
<h3 class="title">Notes</h3>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
This function expects a <span class="type"><a href="language.types.string.html" class="type string">string</a></span> to be useful, so for example passing
in an <span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span> may not return the expected result. However, also note that
HTML forms will result in numeric strings and not integers. See also the
<a href="language.types.html" class="link">types</a> section of the manual.
</p>
</p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>: <p class="para">
If an <span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span> between -128 and 255 inclusive is provided, it is interpreted as
the ASCII value of a single character (negative values have 256 added in order to allow
characters in the Extended ASCII range). Any other integer is interpreted as a string
containing the decimal digits of the integer.</p></p></blockquote>
</div>
<div class="refsect1 seealso" id="refsect1-function.ctype-digit-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.ctype-alnum.html" class="function" rel="rdfs-seeAlso">ctype_alnum()</a> - Check for alphanumeric character(s)</span></li>
<li class="member"> <span class="function"><a href="function.ctype-xdigit.html" class="function" rel="rdfs-seeAlso">ctype_xdigit()</a> - Check for character(s) representing a hexadecimal digit</span></li>
<li class="member"> <span class="function"><a href="function.is-numeric.html" class="function" rel="rdfs-seeAlso">is_numeric()</a> - Finds whether a variable is a number or a numeric string</span></li>
<li class="member"> <span class="function"><a href="function.is-int.html" class="function" rel="rdfs-seeAlso">is_int()</a> - Find whether the type of a variable is integer</span></li>
<li class="member"> <span class="function"><a href="function.is-string.html" class="function" rel="rdfs-seeAlso">is_string()</a> - Find whether the type of a variable is string</span></li>
</ul>
</p>
</div>
</div><hr /><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="function.ctype-cntrl.html">ctype_cntrl</a></div>
<div class="next" style="text-align: right; float: right;"><a href="function.ctype-graph.html">ctype_graph</a></div>
<div class="up"><a href="ref.ctype.html">Ctype Functions</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div></body></html>
