PHP advanced filter

PHP Advanced Filter

Detect whether a number is within a range

The following example uses the filter_var() function to detect whether an INT type variable is within a range Within 1 to 200:

Example

<?php
 $int = 122;
 $min = 1;
 $max = 200;
 
 if (filter_var($int, FILTER_VALIDATE_INT, array("options" => array("min_range"=>$min, "max_range"=>$max))) === false) {
     echo("变量值不在合法范围内");
 } else {
     echo("变量值在合法范围内");
 }
 ?>

Detect IPv6 address

The following example uses the filter_var() function to detect Whether an $ip variable is an IPv6 address:

Example

<?php
 $ip = "2001:0db8:85a3:08d3:1319:8a2e:0370:7334";
 
 if (!filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6) === false) {
     echo("$ip 是一个 IPv6 地址");
 } else {
     echo("$ip 不是一个 IPv6 地址");
 }
 ?>

Check URL - must contain QUERY_STRING (query string)

The following example uses the filter_var() function to detect whether $url contains the query string:

Example

<?php
 $url = "http://www.runoob.com";
 
 if (!filter_var($url, FILTER_VALIDATE_URL, FILTER_FLAG_QUERY_REQUIRED) === false) {
     echo("$url 是一个合法的 URL");
 } else {
     echo("$url 不是一个合法的 URL");
 }
 ?>

Remove ASCII values ​​greater than 127 Characters

The following example uses the filter_var() function to remove characters with an ASCII value greater than 127 in the string. It can also remove HTML tags:

Example

<?php
 $str = "<h1>Hello WorldÆØÅ!</h1>";
 
 $newstr = filter_var($str, FILTER_SANITIZE_STRING, FILTER_FLAG_STRIP_HIGH);
 echo $newstr;
 ?>

PHP Filter Reference Manual

You can also view the specific application of the filter by visiting the PHP Filter Reference Manual of this site .

The reference manual contains a brief description and usage examples of filter parameters!