php-doc-en/reference/strings/functions/strpos.xml

<?xml version="1.0" encoding="iso-8859-1"?>
<!-- $Revision: 1.15 $ -->
<refentry xmlns="http://docbook.org/ns/docbook" xml:id="function.strpos">
 <refnamediv>
  <refname>strpos</refname>
  <refpurpose>Find position of first occurrence of a string</refpurpose>
 </refnamediv>
 
 <refsect1 role="description">
  &reftitle.description;
  <methodsynopsis>
   <type>int</type><methodname>strpos</methodname>
   <methodparam><type>string</type><parameter>haystack</parameter></methodparam>
   <methodparam><type>mixed</type><parameter>needle</parameter></methodparam>
   <methodparam choice="opt"><type>int</type><parameter>offset</parameter></methodparam>
  </methodsynopsis>
  <para>
   Returns the numeric position of the first occurrence of
   <parameter>needle</parameter> in the <parameter>haystack</parameter>
   string.  Unlike the <function>strrpos</function> before PHP 5, this
   function can take a full string as the <parameter>needle</parameter>
   parameter and the entire string will be used.
  </para>
 </refsect1>

 <refsect1 role="parameters">
  &reftitle.parameters;
  <para>
   <variablelist>
    <varlistentry>
     <term><parameter>haystack</parameter></term>
     <listitem>
      <para>
       The string to search in
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>needle</parameter></term>
     <listitem>
      <para>
       If <parameter>needle</parameter> is not a string, it is converted
       to an integer and applied as the ordinal value of a character.
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>offset</parameter></term>
     <listitem>
      <para>
       The optional <parameter>offset</parameter> parameter allows you
       to specify which character in <parameter>haystack</parameter> to
       start searching. The position returned is still relative to the
       beginning of <parameter>haystack</parameter>.
      </para>
     </listitem>
    </varlistentry>
   </variablelist>
  </para>
 </refsect1>

 <refsect1 role="returnvalues">
  &reftitle.returnvalues;
  <para>
   Returns the position as an integer. If <parameter>needle</parameter> is
   not found, <function>strpos</function> will return <type>boolean</type>
   &false;.
  </para>
  &return.falseproblem;
 </refsect1>

 <refsect1 role="examples">
  &reftitle.examples;
  <para>
   <example>
    <title><function>strpos</function> examples</title>
    <programlisting role="php">
<![CDATA[
<?php
$mystring = 'abc';
$findme   = 'a';
$pos = strpos($mystring, $findme);

// Note our use of ===.  Simply == would not work as expected
// because the position of 'a' was the 0th (first) character.
if ($pos === false) {
    echo "The string '$findme' was not found in the string '$mystring'";
} else {
    echo "The string '$findme' was found in the string '$mystring'";
    echo " and exists at position $pos";
}

// We can search for the character, ignoring anything before the offset
$newstring = 'abcdef abcdef';
$pos = strpos($newstring, 'a', 1); // $pos = 7, not 0
?>
]]>
    </programlisting>
   </example>
  </para>
 </refsect1>

 <refsect1 role="notes">
  &reftitle.notes;
  &note.bin-safe;
 </refsect1>

 <refsect1 role="seealso">
  &reftitle.seealso;
  <para>
   <simplelist>
    <member><function>strrpos</function></member>
    <member><function>stripos</function></member>
    <member><function>strripos</function></member>
    <member><function>strrchr</function></member>
    <member><function>substr</function></member>
    <member><function>stristr</function></member>
    <member><function>strstr</function></member>
   </simplelist>
  </para>
 </refsect1>

</refentry>

<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"../../../../manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->