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Home Backend Development PHP Tutorial 弱弱的一个问题

弱弱的一个问题

Jun 23, 2016 pm 01:56 PM

$foo = array("bob", "fred", "jussi", "jouni", "egon", "marliese");
$bar = each($foo);
print_r($bar);
?>

哪位大大能详细解析一下吧=-=     搞不懂那个输出的结果


回复讨论(解决方案)

php系统函数没啥好解释的,知道怎么用就行
返回 array 数组中当前指针位置的键/值对并向前移动数组指针。键值对被返回为四个单元的数组,键名为 0,1,key 和 value。单元 0 和 key 包含有数组单元的键名,1 和 value 包含有数据。 

如果内部指针越过了数组的末端,则 each() 返回 FALSE。 

手册不是有说明吗,怎么搞不懂啊。

 $foo = array("bob", "fred", "jussi", "jouni", "egon", "marliese");
foreach ($foo,$key,$value)
{
   echo "下标".$key."值:".$value;
}
//下面的应该会输出第一个元素
 $bar = each($foo);
 print_r($bar);
 ?>

php系统函数没啥好解释的,知道怎么用就行
返回 array 数组中当前指针位置的键/值对并向前移动数组指针。键值对被返回为四个单元的数组,键名为 0,1,key 和 value。单元 0 和 key 包含有数组单元的键名,1 和 value 包含有数据。 

如果内部指针越过了数组的末端,则 each() 返回 FALSE。 



为啥0和key昨键名?而且键值相同,1和value也同理

php 的数组有两种表现形式:
一种是下标数组,以数字为下标访问
一种是关联数组,也名称为关联键访问
对于同一个数组元素,只能用之一

正因为如此 each 函数以两种形式返回数组的信息,供你选择使用

php 的数组有两种表现形式:
一种是下标数组,以数字为下标访问
一种是关联数组,也名称为关联键访问
对于同一个数组元素,只能用之一

正因为如此 each 函数以两种形式返回数组的信息,供你选择使用



key和0   value和1都是系统默认的吧

对是默认的
0 和 1 一对、key 和 value 一对




对是默认的
0 和 1 一对、key 和 value 一对


thanks
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