php遍历数组的方法分享

在PHP中数组分为两类： 数字索引数组和关联数组。
其中数字索引数组和C语言中的数组一样，下标是为0，1，2…
而关联数组下标可能是任意类型，与其它语言中的hash，map等结构相似。
方法1：foreach

<?php 
$sports = array( 
'football' => 'good', 
'swimming' => 'very well', 
'running' => 'not good'); 
foreach ($sports as $key => $value) { 
echo $key.": ".$value."<br />"; 
} 
?>

输出结果：
football: good
swimming: very well
running: not good
方法2：each

<?php 
$sports = array( 
'football' => 'good', 
'swimming' => 'very well', 
'running' => 'not good'); 
while (!!$elem = each($sports)) { 
echo $elem['key'].": ".$elem['value']."<br />"; 
} 
?>

输出结果：
football: good
swimming: very well
running: not good

方法3：list & each

<?php 
$sports = array( 
'football' => 'good', 
'swimming' => 'very well', 
'running' => 'not good'); 
while (!!list($key, $value) = each($sports)) { 
echo $key.": ".$value."<br />"; 
} 
?>

输出结果：
football: good
swimming: very well
running: not good