PHP foreach循环 总结

foreach(array_expression_r_r as $value)
statement

<?php
$arr=array(1,2,3,4);
foreach($arr as $value)
{
$value=$value*2;
}
//$arr is now array(2,4,6,8)
?>

foreach(array_expression_r_r as $key=> $value)
statement

<?php
foreach(array(1,2,3,4) as $value)
{$value=$value*2;}
?>