SQL IP to BigInt IP地址转换数字

http://blog.joycode.com/ghj/tags/287.aspx

前一篇博客 IP to Integer 提供的 SQL 函数是 IP 转换成 Integer 的方法。 Integer 的最大值为： 2147483647（2^31 - 1）。按照 IP 转换成整数的算法，会算出来大于这个值的，所以之前提供的 IP 转换成 Integer 的方法会算出负值。

下面是 IP to BigInt 的转换算法， 这时候运算就不会小于零。

CREATE FUNCTION dbo.ipStringToBigInt 
( 
    @ip CHAR(15) 
) 
RETURNS bigint 
AS 
BEGIN 
    DECLARE @rv bigint, 
        @o1 bigint, 
        @o2 INT, 
        @o3 INT, 
        @o4 INT
 
    SELECT 
        @o1 = CONVERT(INT, PARSENAME(@ip, 4)), 
        @o2 = CONVERT(INT, PARSENAME(@ip, 3)), 
        @o3 = CONVERT(INT, PARSENAME(@ip, 2)), 
        @o4 = CONVERT(INT, PARSENAME(@ip, 1)) 
 
    IF (@o1 BETWEEN 0 AND 255) 
        AND (@o2 BETWEEN 0 AND 255) 
        AND (@o3 BETWEEN 0 AND 255) 
        AND (@o4 BETWEEN 0 AND 255) 
    BEGIN      
 
        SET @rv = (@o1 * 16777216)  +  
            (@o2 * 65536) +  
            (@o3 * 256) + 
            (@o4) 
    END 
    ELSE 
        SET @rv = -1 
    RETURN @rv 
END
go 



CREATE FUNCTION dbo.ipBigIntToString 
( 
    @ip bigint 
) 
RETURNS CHAR(15) 
AS 
BEGIN 
    DECLARE @o1 INT, 
        @o2 INT, 
        @o3 INT, 
        @o4 INT 
 
    IF @ip > 4294967295 RETURN '255.255.255.255' 
    IF @ip <= 0 RETURN '0.0.0.0' 
 
    SET @o1 = @ip / 16777216
 
    SET @ip = @ip % 16777216 
    SET @o2 = @ip / 65536 
    SET @ip = @ip % 65536 
    SET @o3 = @ip / 256 
    SET @ip = @ip % 256 
    SET @o4 = @ip 
 
    RETURN 
        CONVERT(VARCHAR(4), @o1) + '.' + 
        CONVERT(VARCHAR(4), @o2) + '.' + 
        CONVERT(VARCHAR(4), @o3) + '.' + 
        CONVERT(VARCHAR(4), @o4) 
END

go 

-- 调用例子
select dbo.ipBigIntToString(3708279131)
select dbo.ipStringToBigInt('221.7.217.91')

IP to Integer
有时候我们要判断某个IP是否在某个段内，如何实现呢？ 一个简单办法就是把IP转换成Integer，然后判断整数是否在某个范围内就可以实现这个判断。
转换的算法如下：
比如我们要转换的IP为： 058.062.042.000
First Octet: 058 
Second Octet: 062 
Third Octet: 042 
Fourth Octet: 000 
计算公式如下： 
(first octet * 256³) + (second octet * 256²) + (third octet * 256) + (fourth octet) 
=  (first octet * 16777216) + (second octet * 65536) + (third octet * 256) + (fourth octet) 
=  (058 * 16777216) + (062 * 65536) + (042 * 256) + (000) 
=  977152512 
网上有现成的服务，比如下面这个地址：
http://www.aboutmyip.com/AboutMyXApp/IP2Integer.jsp
SQL Server 的一个例子如下：
CREATE FUNCTION dbo.ipStringToInt 
( 
    @ip CHAR(15) 
) 
RETURNS INT 
AS 
BEGIN 
    DECLARE @rv INT, 
        @o1 INT, 
        @o2 INT, 
        @o3 INT, 
        @o4 INT, 
        @base INT 
 
    SELECT 
        @o1 = CONVERT(INT, PARSENAME(@ip, 4)), 
        @o2 = CONVERT(INT, PARSENAME(@ip, 3)), 
        @o3 = CONVERT(INT, PARSENAME(@ip, 2)), 
        @o4 = CONVERT(INT, PARSENAME(@ip, 1)) 
 
    IF (@o1 BETWEEN 0 AND 255) 
        AND (@o2 BETWEEN 0 AND 255) 
        AND (@o3 BETWEEN 0 AND 255) 
        AND (@o4 BETWEEN 0 AND 255) 
    BEGIN      
        SELECT @base = CASE 
            WHEN @o1 < 128 THEN 
                (@o1 * 16777216) 
            ELSE 
                -(256 - @o1) * 16777216 
            END 
     
        SET @rv = @base +  
            (@o2 * 65536) +  
            (@o3 * 256) + 
            (@o4) 
    END 
    ELSE 
        SET @rv = -1 
    RETURN @rv 
END
go
调用范例：
select dbo.ipStringToInt('058.062.042.000')
整数转换如下：
CREATE FUNCTION dbo.ipIntToString 
( 
    @ip INT 
) 
RETURNS CHAR(15) 
AS 
BEGIN 
    DECLARE @o1 INT, 
        @o2 INT, 
        @o3 INT, 
        @o4 INT 
 
    IF ABS(@ip) > 2147483647 
        RETURN '255.255.255.255' 
 
    SET @o1 = @ip / 16777216 
 
    IF @o1 = 0 
        SELECT @o1 = 255, @ip = @ip + 16777216 
 
    ELSE IF @o1 < 0 
    BEGIN 
        IF @ip % 16777216 = 0 
            SET @o1 = @o1 + 256 
        ELSE 
        BEGIN 
            SET @o1 = @o1 + 255 
            IF @o1 = 128 
                SET @ip = @ip + 2147483648 
            ELSE 
                SET @ip = @ip + (16777216 * (256 - @o1)) 
        END 
    END 
    ELSE 
    BEGIN 
        SET @ip = @ip - (16777216 * @o1) 
    END 
 
    SET @ip = @ip % 16777216 
    SET @o2 = @ip / 65536 
    SET @ip = @ip % 65536 
    SET @o3 = @ip / 256 
    SET @ip = @ip % 256 
    SET @o4 = @ip 
 
    RETURN 
        CONVERT(VARCHAR(4), @o1) + '.' + 
        CONVERT(VARCHAR(4), @o2) + '.' + 
        CONVERT(VARCHAR(4), @o3) + '.' + 
        CONVERT(VARCHAR(4), @o4) 
END
go
调用范例：
select dbo.ipIntToString(977152512)
C# 的例子如下：
using System;
using System.Net;

namespace ConsoleApplication1
{
    class Program
    {
        static long ToInt(string addr)
        {
            return BitConverter.ToInt32(IPAddress.Parse(addr).GetAddressBytes(), 0); 
        }

        static string ToAddr(long address)
        {
            return IPAddress.Parse(address.ToString()).ToString();
            // This also works: 
            // return new IPAddress((uint) IPAddress.HostToNetworkOrder( 
            //    (int) address)).ToString(); 
        }

        static void Main(string[] args)
        {
            Console.WriteLine(ToInt("64.233.187.99"));
            Console.WriteLine(ToAddr(1089059683)); 

            Console.ReadLine();
        }
    }
}
参考资料：
How should I store an IP address in SQL Server? 
http://sqlserver2000.databases.aspfaq.com/how-should-i-store-an-ip-address-in-sql-server.html
How to convert an IPv4 address into a integer in C#? 
http://stackoverflow.com/questions/461742/how-to-convert-an-ipv4-address-into-a-integer-in-c