php-doc-en/language/control-structures/continue.xml

<?xml version="1.0" encoding="utf-8"?>
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<sect1 xml:id="control-structures.continue" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
 <title><literal>continue</literal></title>
 <?phpdoc print-version-for="continue"?>
 <simpara>
  <literal>continue</literal> is used within looping structures to
  skip the rest of the current loop iteration and continue execution
  at the condition evaluation and then the beginning of the next iteration.
 </simpara>
 <note>
  <simpara>
   Note that in PHP the
   <link linkend="control-structures.switch">switch</link> statement is
   considered a looping structure for the purposes of
   <literal>continue</literal>.
  </simpara>
 </note>
 <simpara>
  <literal>continue</literal> accepts an optional numeric argument
  which tells it how many levels of enclosing loops it should skip
  to the end of. The default value is <literal>1</literal>, thus skipping
  to the end of the current loop.
 </simpara>
 <para>
  <informalexample>
   <programlisting role="php">
<![CDATA[
<?php
while (list($key, $value) = each($arr)) {
    if (!($key % 2)) { // skip odd members
        continue;
    }
    do_something_odd($value);
}

$i = 0;
while ($i++ < 5) {
    echo "Outer<br />\n";
    while (1) {
        echo "Middle<br />\n";
        while (1) {
            echo "Inner<br />\n";
            continue 3;
        }
        echo "This never gets output.<br />\n";
    }
    echo "Neither does this.<br />\n";
}
?>
]]>
   </programlisting>
  </informalexample>
 </para>
 <para>
  Omitting the semicolon after <literal>continue</literal> can lead to
  confusion. Here's an example of what you shouldn't do.
 </para>
 <para>
  <informalexample>
   <programlisting role="php">
<![CDATA[
<?php
for ($i = 0; $i < 5; ++$i) {
    if ($i == 2)
        continue
    print "$i\n";
}
?>
]]>
   </programlisting>
   <para>
    One can expect the result to be:
   </para>
   <screen>
<![CDATA[
0
1
3
4
]]>
   </screen>
   <para>
    but this script will output:
   </para>
   <screen>
<![CDATA[
2
]]>
   </screen>
   <para>
    because the entire <literal>continue print "$i\n";</literal> is evaluated
    as a single expression, and so <function>print</function> is called only
    when <literal>$i == 2</literal> is true. (The return value of
    <literal>print</literal> is passed to <literal>continue</literal> as the
    numeric argument.)
   </para>
  </informalexample>
 </para>
 <para>
  <table>
   <title>Changelog for <literal>continue</literal></title>
   <tgroup cols="2">
    <thead>
     <row>
      <entry>&Version;</entry>
      <entry>&Description;</entry>
     </row>
    </thead>
    <tbody>
     <row>
      <entry>5.4.0</entry>
      <entry>
       <literal>continue 0;</literal> is no longer valid. In previous versions it was interpreted
       the same as <literal>continue 1;</literal>.
      </entry>
     </row>
     <row>
      <entry>5.4.0</entry>
      <entry>
       Removed the ability to pass in variables (e.g., <literal>$num = 2; continue $num;</literal>)
       as the numerical argument.
      </entry>
     </row>
    </tbody>
   </tgroup>
  </table>
 </para>
</sect1>

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