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PHP数组操作获取数组最后一个值的方法_PHP

Jun 01, 2016 pm 02:35 PM

php开发过程中,可能经常需要对取出的数组要获取数组的最后健或值。在这里总结了三个方法,并且跟据他们三个方法在一些情况下如何使用的条件限制进行了说明。

<&#63;php 
$array=array(1,2,3,4,5); 
echo $array[count($array)-1];//计算数组长度,然后获取数组最后一个元素,如果数组中最后一个元素含有非数字键名,结果可能跟预期不符合 
//适用于键名为数字的数组 
echo '<br>'; 
echo end($array);//将数组的内部指针指向最后一个单元,适用于所有数组 
echo '<br>'; 
rsort($array);//对数组逆向排序,如果数组中含有字母或汉字,结果可能不符合预期,最适用于数字数组 
echo $array[0]; 
&#63;>
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总体来说,php的内置函数end还是最好的方法的了。大家可以测试下。

PHP取值很容易,可以使用循环遍历、类指针(个人称之),但是如果去数组最后一个值的时候也采用遍历的话是不是消耗了很多性能啊??

下面有三种取值方法可以更好的取出数组的最后一个值:

<&#63;PHP
$array = array(1,2,4,6,8);
echo end($array);
&#63;> 

<&#63;PHP
$array = array(1,2,4,6,8);
echo array_pop($array);
&#63;> 

<&#63;PHP
$array = array(1,2,4,6,8);
$k = array_slice($array,-1,1);
print_r($k);  //结果是一维数组
&#63;> 
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这是三个函数的取值方法,直接有效,按需选择吧

2012年3月31日编辑:第二种方法有一种弊端,Array_pop()函数会把原来的数据的最后一个数“取出来”,也就是相当于剪切的意思,原来的数据中将不不再有最后一个值了

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