php 函数积累

array_slice()
<?php
$a=array("red","green","blue","yellow","brown");
print_r(array_slice($a,2));    //Array ( [0] => blue [1] => yellow [2] => brown )
?>

trim()
<?php 
 $str='1,2,3,4,';
 trim($str,',');
?>

array_filter($array)
去除数组中值为 ' ' 和 NULL 和 false   的项