通过PHP current函数获取未知字符键名数组第一个元素的值
在开发中经常遇到这样问题,获取数组第一个元素的值,如果是数字索引那还好,直接$array[0],如果键名是字符串,你又未知这个字符串呢?用current()函数就可以做
关于current()函数:
每个数组中都有一个内部的指针指向它“当前的”单元,初始指向插入到数组中的第一个单元。用current()获取。
类似函数:
end() 将array的内部指针移动到最后一个单元并返回其值。
next()返回数组内部指针指向的下一个单元的值,香港服务器,或当没有更多单元时返回FALSE。
prev()返回数组内部指针指向的前一个单元的值,美国空间,或当没有更多单元时返回FALSE。
reset() 将array的内部指针倒回到第一个单元并返回第一个数组单元的值,如果数组为空则返回FALSE。
看下面PHP案例:
复制代码 代码如下:
$arr = array("a"=>"php","java","c");
echo current($arr); //php
echo next($arr); //java
echo prev($arr); //php 指向上一单元的值,香港服务器,所以又为php了
echo end($arr); //c
?>
很好用且很有用的几个php函数,反正我是记住了。

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