php in_array(mixed $needle, array $haystack[, bool $strict = FALSE] )
注意： 一、如果$needle 是字符串，则比较是区分大小写的。
二、如果$strict = TRUE 则in_array 会比较$needle 和$haystack 的类型是否一致，不一致，则返回FALSE
1 //例一、in_array 严格类型检查例子 2 <?php 3 ????$a = array(‘1.12‘, 2.16, 3.18); 4 ????if(in_array(‘2.16‘, $a, true)) 5 ????{ 6 ????????echo "‘2.16‘ found with strict check\n"; ?????????7 ????} 8 ????if(in_array(3.18, $a, true)) 9 ????{10 ????????echo "3.18 found with strict check\n"; ????????11 ????}12 ?>13 //output 3.18 found with struct check14 //例二、in_array()中用数组作为$needle15 ?<?php16 ????$a = array(array(‘p‘, ‘h‘), array(‘j‘, ‘q‘), ‘o‘);17 ????if(in_array(array(‘p‘, ‘h‘), $a))18 ????{19 ????????echo "‘ph‘ was found\n";20 ????}21 ????if(in_array(array(‘f‘, ‘i‘), $a))22 ????{23 ????????echo "‘fi‘ was found\n";24 ????}25 ????if(in_array(‘o‘, $a))26 ????{27 ????????echo "‘fi‘ was found\n";28 ????}29 ??>30 //output ‘ph‘ was found31 ?????????????‘o‘ was found32 33 ????PHP语法-该注意的细节
原文地址：https://www.cnblogs.com/jasonxu19900827/p/9063202.html