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<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.6 $ -->
<!-- splitted from ./en/functions/strings.xml, last change in rev 1.2 -->
<refentry id="function.ltrim">
<refnamediv>
<refname>ltrim</refname>
<refpurpose>
Strip whitespace (or other characters) from the beginning of a string
</refpurpose>
</refnamediv>
<refsect1>
<title>Description</title>
<methodsynopsis>
<type>string</type><methodname>ltrim</methodname>
<methodparam><type>string</type><parameter>str</parameter></methodparam>
<methodparam choice="opt"><type>string</type><parameter>charlist</parameter></methodparam>
</methodsynopsis>
<note>
<simpara>
The second parameter was added in PHP 4.1.0
</simpara>
</note>
<para>
This function returns a string with whitespace stripped from the
beginning of <parameter>str</parameter>.
Without the second parameter,
<function>ltrim</function> will strip these characters:
<!-- sorted by importance. Printed 3 times: trim, ltrim, rtrim -->
<itemizedlist>
<listitem>
<simpara>
" " (<acronym>ASCII</acronym> <literal>32</literal>
(<literal>0x20</literal>)), an ordinary space.
</simpara>
</listitem>
<listitem>
<simpara>
"\t" (<acronym>ASCII</acronym> <literal>9</literal>
(<literal>0x09</literal>)), a tab.
</simpara>
</listitem>
<listitem>
<simpara>
"\n" (<acronym>ASCII</acronym> <literal>10</literal>
(<literal>0x0A</literal>)), a new line (line feed).
</simpara>
</listitem>
<listitem>
<simpara>
"\r" (<acronym>ASCII</acronym> <literal>13</literal>
(<literal>0x0D</literal>)), a carriage return.
</simpara>
</listitem>
<listitem>
<simpara>
"\0" (<acronym>ASCII</acronym> <literal>0</literal>
(<literal>0x00</literal>)), the <literal>NUL</literal>-byte.
</simpara>
</listitem>
<listitem>
<simpara> <!-- not \v, since not supported by PHP -->
"\x0B" (<acronym>ASCII</acronym> <literal>11</literal>
(<literal>0x0B</literal>)), a vertical tab.
</simpara>
</listitem>
</itemizedlist>
</para>
<para>
You can also specify the characters you want to strip, by means
of the <parameter>charlist</parameter> parameter.
Simply list all characters that you want to be stripped. With
<literal>..</literal> you can specify a range of characters.
</para>
<example>
<title>Usage example of <function>ltrim</function></title>
<programlisting role="php">
<![CDATA[
<?php
$text = "\t\tThese are a few words :) ... ";
$trimmed = ltrim($text);
// $trimmed = "These are a few words :) ... "
$trimmed = ltrim($text, " \t.");
// $trimmed = "These are a few words :) ... "
$clean = ltrim($binary, "\x00..\x1F");
// trim the ASCII control characters at the beginning of $binary
// (from 0 to 31 inclusive)
?>
]]>
</programlisting>
</example>
<para>
See also <function>trim</function> and <function>rtrim</function>.
</para>
</refsect1>
</refentry>
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