[TOC] ## 概述 ``` filter_var ( mixed $variable [, int $filter = FILTER_DEFAULT [, mixed $options ]] ) : mixed return 值或者 false ``` ## 实例 ## 基础实力 ``` $a="http:/www.baidu.com"; // 消毒 $filter_a = filter_var($a, FILTER_SANITIZE_URL); // 判断 if (filter_var($filter_a,FILTER_VALIDATE_URL)===false){ die("failed"); }else{ die("success"); } // output: failed ``` ## 对变量进行消毒 ``` $a = '(bogus@example.org) '; // 对 $a 虑空 $sanitized_a = filter_var($a, FILTER_SANITIZE_EMAIL); // output: joe@example.org // 在进行比较 if (filter_var($sanitized_a, FILTER_VALIDATE_EMAIL)) { echo "Yes"; }else{ echo "No"; } ``` ## 使用options ``` $options = array( 'options' => array( 'default' => 3, // 值返回如果筛选失败 'min_range' => 0 ), 'flags' =>FILTER_FLAG_ALLOW_OCTAL, // 返回值从 false 变为 null ); $var = filter_var(0755, FILTER_VALIDATE_INT, $options); var_dump($var); // 493 ```