[PHP] 常用的Regular Expression

$ipAddress = "/^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])?$/";

$domain = "/^(?:(([a-z]{1})|([a-z]{1}[a-z]{1})|([a-z]{1}[0-9]{1})|([0-9]{1}[a-z]{1})|([a-z0-9][a-z0-9\-\_]{1,61}[a-z0-9]))\.)+([a-z]{2,6}|[a-z0-9-]{2,30}\.[a-z]{2,3})$/";

$macAddress = "/^\s*([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})\s*$/";