Compzone.Org :: Podręcznik PHP :: ip2long

Podręcznik PHP
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ip2long

(PHP 4, PHP 5)

ip2long -- Converts a string containing an (IPv4) Internet Protocol dotted address into a proper address

Description

int ip2long ( string ip_address )

The function ip2long() generates an IPv4 Internet network address from its Internet standard format (dotted string) representation. If ip_address is invalid then -1 is returned. Note that -1 does not evaluate as FALSE in PHP.

Notatka: As of PHP 5.0.0 ip2long() returns FALSE when ip_address is invalid.

Przykład 1. ip2long() Example

<?php

                $ip = gethostbyname('www.example.com');

                $out = "The following URLs are equivalent:<br />\n";

                $out .= 'http://www.example.com/, http://' . $ip . '/, and http://' . sprintf("%u", ip2long($ip)) . "/<br />\n";


                echo $out;
?>

Notatka: Because PHP's integer type is signed, and many IP addresses will result in negative integers, you need to use the "%u" formatter of sprintf() or printf() to get the string representation of the unsigned IP address.

This second example shows how to print a converted address with the printf() function in both PHP 4 and PHP 5:

Przykład 2. Displaying an IP address

<?php

                $ip   = gethostbyname('www.example.com');

                $long = ip2long($ip);

                

                if ($long == -1 || $long === FALSE) {

                    echo 'Invalid IP, please try again';


                } else {

                    echo $ip   . "\n";           // 192.0.34.166

                    echo $long . "\n";           // -1073732954

                    printf("%u\n", ip2long($ip)); // 3221234342
}

                ?>

ip2long() should not be used as the sole form of IP validation. Combine it with long2ip():

Przykład 3. IP validation

<?php
// make sure IPs are valid. also converts a non-complete IP into


                // a proper dotted quad as explained below.
$ip = long2ip(ip2long("127.0.0.1")); // "127.0.0.1"

                $ip = long2ip(ip2long("10.0.0")); // "10.0.0.0"
$ip = long2ip(ip2long("10.0.256")); // "10.0.1.0"

                ?>

ip2long() will also work with non-complete IP addresses. Read http://publibn.boulder.ibm.com/doc_link/en_US/a_doc_lib/libs/commtrf2/inet_addr.htm for more info.

Notatka: ip2long() will return FALSE for the IP 255.255.255.255 in PHP 5 <= 5.0.2. It was fixed in PHP 5.0.3 where it returns -1 (same as PHP 4).

See also long2ip() and sprintf().

Poprzedni	Spis treści	Następny
inet_pton	Początek rozdziału	long2ip