PHP比较IP大小

function cmpLoginIP($a, $b)
{
    return bindec(decbin(ip2long($a['loginIp']))) > bindec(decbin(ip2long($b['loginIp'])));
}

function cmpLoginIPDesc($a, $b)
{
    return bindec(decbin(ip2long($b['loginIp']))) > bindec(decbin(ip2long($a['loginIp'])));
}