Advanced Filters for Beginners to PHP

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 1 to 200 :

 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 a $ip variable is an IPv6 address:

Detect URL - must contain QUERY_STRING (query string)

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

Remove characters with ASCII values greater than 127

The following example uses the filter_var() function to remove ASCII from the string Characters with a value greater than 127, it can also remove HTML tags:

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