Fomo3D系统APP开发制作

php中foreach()函数的用法以及Fomo3D系统APP开发制作源代码介绍T：/ I8O-2853-296O /黎灿+foreach()有两种用 法：

1： foreach(array_name as $value) { statement; }

这里的array_name是你要遍历的数组名，每次循环中，array_name数组的当前元素的值被赋给$value,并且数组内部的下标向下移一 步，也就是下次循环回得到下一个元素。

2：foreach(array_name as $key => $value) { statement; }

这里跟第一种方法的区别就是多了个$key,也就是除了把当前元素的值赋给$value外，当前元素的键值也会在每次循环中被赋给变量$key。键值可以 是下标值，也可以是字符串。比如book[0]=1中的“0”，book[id]="001"中的“id”.

示范用法的更多例子：

<?php
/-------------------------------------------------------------------------/
/ foreach example 1: value only /
echo "foreach example 1: value only ".'
';

$a = array(1, 2, 3, 17);

foreach ($a as $v) {
echo "Current value of "$a: $v".'
';
}

/-------------------------------------------------------------------------/
/ foreach example 2: value (with key printed for illustration) /
echo '
'.'
'."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) {

echo ""$a[$i] => $v".'<br />';$i++;

}

/-------------------------------------------------------------------------/
/ foreach example 3: key and value /
echo '
'.'
'."foreach example 3: key and value ".'
';

$a = array(

"one" => 1,"two" => 2,"three" => 3,"seventeen" => 17

);

foreach ($a as $k => $v) {

echo ""$a[$k] => $v".'<br />';

}

/-------------------------------------------------------------------------/
/ foreach example 4: multi-dimensional arrays /
echo '
'.'
'."foreach example 4: multi-dimensional arrays ".'
';

$a = array();
$a0 = "a";
$a0 = "b";
$a1 = "y";
$a1 = "z";

foreach ($a as $v1) {

foreach ($v1 as $v2) {    echo "$v2"n";}

}

/-------------------------------------------------------------------------/
/ foreach example 5: dynamic arrays /
echo '
'.'
'."foreach example 5: dynamic arrays ".'
';

foreach (array(1, 2, 3, 4, 5) as $v) {

echo "$v"n";

}
?>

结果如下:

foreach example 1: value only
Current value of $a: 1
Current value of $a: 2
Current value of $a: 3
Current value of $a: 17

foreach example 2: value (with key printed for illustration)
$a[0] => 1
$a[1] => 2
$a[2] => 3
$a[3] => 17

foreach example 3: key and value
$a[one] => 1
$a[two] => 2
$a[three] => 3
$a[seventeen] => 17

foreach example 4: multi-dimensional arrays
a b y z

foreach example 5: dynamic arrays
1 2 3 4 5

/ foreach example 3: key and value /
echo '
'.'
'."foreach example 3: key and value ".'
';

$messageNav['首页'] =ROOT_PATH;

$messageNav['人才交流'] ="#"

$messageNav['动态专栏'] ="hragent/cn/"

<?php $i = 0;foreach ($messageNav as $key=>$value):?>

<?php if ($i != count($messageNav) - 1):?>