PHP 遍历数组语句总结(foreach,for,list,each)

PHP 遍历数组语句总结(foreach,for,list,each)

foreach来访问, 遍历的顺序是固定的么? 以什么顺序遍历呢?

比如:

代码如下

<?php

$colors= array('red','blue','green','yellow');

foreach ($colors as $color){

//add your codes

}

?>

例2

$capitals= array("Ohio"=> "Columbus","Towa"=> "Des Moines","Arizona"=> "Phoenix");

foreach($capitals as $key=> $val){

//add your codes

}

while()

while() 通常和 list(),each()配合使用。

#example2:

代码如下

<?php

$colors = array('red','blue','green','yellow');

while(list($key,$val) = each($colors)) {

echo "Other list of $val.<br />";

}

?>

显示结果:

Other list of red.

Other list of blue.

Other list of green.

Other list of yellow.

3. for()

#example3:

代码如下

<?php

$arr = array ("0" => "zero","1" => "one","2" => "two");

for ($i = 0;$i < count($arr); $i++) {

$str = $arr[$i];

echo "the number is $str.<br />";

}

?>

显示结果:

the number is zero.

the number is one.

the number is two.

========= 以下是函数介绍 ==========

key()

mixed key(array input_array)

key()函数返回input_array中位于当前指针位置的键元素。

#example4

代码如下

<?php

$capitals = array("Ohio" => "Columbus","Towa" => "Des Moines","Arizona" => "Phoenix");

echo "<p>Can you name the capitals of these states?</p>";

while($key = key($capitals)) {

echo $key."<br />";

next($capitals);

//每个key()调用不会推进指针。为此要使用next()函数

}

?>

Can you name the capitals of these states?

Ohio

Towa

Arizona

each() 函数遍历数组

例子 1

代码如下

<?php

$people = array("Peter", "Joe", "Glenn", "Cleveland");

print_r (each($people));

?>

输出:

Array ( [1] => Peter [value] => Peter [0] => 0 [key] => 0 )

子 2

each() 经常和 list() 结合使用来遍历数组。本例与上例类似,不过循环输出了整个数组:

代码如下

复制代码

<?php

$people = array("Peter", "Joe", "Glenn", "Cleveland");

reset($people);

while (list($key, $val) = each($people))

{

echo "$key => $val<br />";

}

?>

输出:

0 => Peter

1 => Joe

2 => Glenn

3 => Cleveland

多维数组的递归遍历

代码如下

<?php

/*

* -------------------------------------------------

* Author :

* Url : www.45it.com* Date : 2011-03-09

* -------------------------------------------------

*/

function arr_foreach ($arr)

{

if (!is_array ($arr))

{

return false;

}

foreach ($arr as $key => $val )

{

if (is_array ($val))

{

arr_foreach ($val);

}

else

{

echo $val.'<br/>';

}

}

}

$arr1 = array (1=>array(11,12,13,14=>array(141,142)),2,3,4,5);

echo '<pre>';

print_r($arr1);

echo '<pre>';

arr_foreach ($arr1);

?>

结果

Array

(

[1] => Array

(

[0] => 11

[1] => 12

[2] => 13

[14] => Array

(

[0] => 141

[1] => 142

)

)

[2] => 2

[3] => 3

[4] => 4

[5] => 5

)

11

12

13

141

142

2

3

4

5