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control-structures.foreach.html
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<HTML
><HEAD
><TITLE
>foreach</TITLE
><META
NAME="GENERATOR"
CONTENT="Modular DocBook HTML Stylesheet Version 1.57"><LINK
REL="HOME"
TITLE="PHP Manual"
HREF="manual.html"><LINK
REL="UP"
TITLE="Control Structures"
HREF="control-structures.html"><LINK
REL="PREVIOUS"
TITLE="for"
HREF="control-structures.for.html"><LINK
REL="NEXT"
TITLE="break"
HREF="control-structures.break.html"><META
NAME="HTTP_EQUIV"
CONTENT="text/html; charset=ISO-8859-1"></HEAD
><BODY
CLASS="sect1"
BGCOLOR="#FFFFFF"
TEXT="#000000"
LINK="#0000FF"
VLINK="#840084"
ALINK="#0000FF"
><DIV
CLASS="NAVHEADER"
><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TH
COLSPAN="3"
ALIGN="center"
>PHP Manual</TH
></TR
><TR
><TD
WIDTH="10%"
ALIGN="left"
VALIGN="bottom"
><A
HREF="control-structures.for.html"
>Prev</A
></TD
><TD
WIDTH="80%"
ALIGN="center"
VALIGN="bottom"
>Chapter 11. Control Structures</TD
><TD
WIDTH="10%"
ALIGN="right"
VALIGN="bottom"
><A
HREF="control-structures.break.html"
>Next</A
></TD
></TR
></TABLE
><HR
ALIGN="LEFT"
WIDTH="100%"></DIV
><DIV
CLASS="sect1"
><H1
CLASS="sect1"
><A
NAME="control-structures.foreach"
><TT
CLASS="literal"
>foreach</TT
></A
></H1
><P
> PHP 4 (not PHP 3) includes a <TT
CLASS="literal"
>foreach</TT
> construct,
much like perl and some other languages. This simply gives an easy
way to iterate over arrays. There are two syntaxes; the second is
a minor but useful extension of the first:
<DIV
CLASS="informalexample"
><A
NAME="AEN3490"
></A
><P
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="programlisting"
> foreach(array_expression as $value) statement
foreach(array_expression as $key => $value) statement
</PRE
></TD
></TR
></TABLE
><P
></P
></DIV
>
</P
><P
> The first form loops over the array given by
<TT
CLASS="literal"
>array_expression</TT
>. On each loop, the value of
the current element is assigned to <TT
CLASS="literal"
>$value</TT
> and
the internal array pointer is advanced by one (so on the next
loop, you'll be looking at the next element).
</P
><P
> The second form does the same thing, except that the current
element's key will be assigned to the variable
<TT
CLASS="literal"
>$key</TT
> on each loop.
</P
><P
> <DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Note: </B
>
When <TT
CLASS="literal"
>foreach</TT
> first starts executing, the
internal array pointer is automatically reset to the first element
of the array. This means that you do not need to call
<A
HREF="function.reset.html"
><B
CLASS="function"
>reset()</B
></A
> before a <TT
CLASS="literal"
>foreach</TT
>
loop.
</P
></BLOCKQUOTE
></DIV
>
</P
><P
> <DIV
CLASS="note"
><BLOCKQUOTE
CLASS="note"
><P
><B
>Note: </B
>
Also note that <TT
CLASS="literal"
>foreach</TT
> operates on a copy of
the specified array, not the array itself, therefore the array
pointer is not modified like with the each construct.
</P
></BLOCKQUOTE
></DIV
>
</P
><P
> You may have noticed that the following are functionally
identical:
<DIV
CLASS="informalexample"
><A
NAME="AEN3508"
></A
><P
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="programlisting"
> reset ($arr);
while (list(, $value) = each ($arr)) {
echo "Value: $value<br>\n";
}
foreach ($arr as $value) {
echo "Value: $value<br>\n";
}
</PRE
></TD
></TR
></TABLE
><P
></P
></DIV
>
The following are also functionally identical:
<DIV
CLASS="informalexample"
><A
NAME="AEN3510"
></A
><P
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="programlisting"
> reset ($arr);
while (list($key, $value) = each ($arr)) {
echo "Key: $key; Value: $value<br>\n";
}
foreach ($arr as $key => $value) {
echo "Key: $key; Value: $value<br>\n";
}
</PRE
></TD
></TR
></TABLE
><P
></P
></DIV
>
</P
><P
> Some more examples to demonstrate usages:
<DIV
CLASS="informalexample"
><A
NAME="AEN3513"
></A
><P
></P
><TABLE
BORDER="0"
BGCOLOR="#E0E0E0"
WIDTH="100%"
><TR
><TD
><PRE
CLASS="programlisting"
> /* foreach example 1: value only */
$a = array (1, 2, 3, 17);
foreach ($a as $v) {
print "Current value of \$a: $v.\n";
}
/* foreach example 2: value (with key printed for illustration) */
$a = array (1, 2, 3, 17);
$i = 0; /* for illustrative purposes only */
foreach($a as $v) {
print "\$a[$i] => $k.\n";
}
/* foreach example 3: key and value */
$a = array (
"one" => 1,
"two" => 2,
"three" => 3,
"seventeen" => 17
);
foreach($a as $k => $v) {
print "\$a[$k] => $v.\n";
}
</PRE
></TD
></TR
></TABLE
><P
></P
></DIV
>
</P
></DIV
><DIV
CLASS="NAVFOOTER"
><HR
ALIGN="LEFT"
WIDTH="100%"><TABLE
WIDTH="100%"
BORDER="0"
CELLPADDING="0"
CELLSPACING="0"
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><A
HREF="control-structures.for.html"
>Prev</A
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="manual.html"
>Home</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><A
HREF="control-structures.break.html"
>Next</A
></TD
></TR
><TR
><TD
WIDTH="33%"
ALIGN="left"
VALIGN="top"
><TT
CLASS="literal"
>for</TT
></TD
><TD
WIDTH="34%"
ALIGN="center"
VALIGN="top"
><A
HREF="control-structures.html"
>Up</A
></TD
><TD
WIDTH="33%"
ALIGN="right"
VALIGN="top"
><TT
CLASS="literal"
>break</TT
></TD
></TR
></TABLE
></DIV
></BODY
></HTML
>