PHP in_array
1.函数的作用:判读一个元素是否在一个数组存在
2.函数的参数:
@param mixed $needle
@param array $array
3. if it’s ok to use isset() function ,then better to use the isset() function instead of in_array() function.
4.
例子一:
1 <?php 2 $arr = [ 3 '1314LoveZhangbiyu', 4 ]; 5 if(in_array(1314,$arr)){ 6 echo '1314'; 7 echo "\n"; 8 } 9 10 if(in_array('1314',$arr)){ 11 echo 'string 1314 is in!'; 12 echo "\n"; 13 }else{ 14 echo 'string 1314 is not in!'; 15 echo "\n"; 16 }
例子二:
1 <?php 2 $a = array('0' => 'Opt 1', '1' => 'Opt 2', '2' => 'Opt 3'); 3 $v = 'sql injection'; 4 var_dump(in_array($v, array_keys($a)));
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