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php数组函数序列之prev()

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Release： 2016-06-01 12:14:43
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prev() 定义和用法
prev() 函数把指向当前元素的指针移动到上一个元素的位置，并返回该元素值。

如果内部指针已经超过数组的第一个元素之前，函数返回 false。

语法
prev(array)参数 描述
array 必需。规定要使用的数组。

说明
prev() 和 next() 的行为类似，不过它将内部指针倒回一位而不是前移一位。

注意：如果数组包含空的单元，或者单元的值是 0 则该函数碰到这些单元也返回 FALSE。要正确遍历可能含有空单元或者单元值为 0 的数组，请参见 each() 函数。

例子
复制代码 代码如下:
$people = array("Peter", "Joe", "Glenn", "Cleveland");

echo current($people) . "
";
echo next($people) . "
";
echo prev($people);
?>

输出：

Peter
Joe
Peter
Related labels：
php array function
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