create function dbo.ConvertIp2NumC(@ipAddr nvarchar(15))
returns bigint
as
begin
    declare @ipPos int, @ipLen int, @ipChar nchar(1), @segNum int, @ipNum bigint
    set @segNum = 0
    set @ipPos = 1
    set @ipNum = 0
    set @ipLen = len(isnull(@ipAddr, ''))
    while @ipPos <= @ipLen begin
        set @ipChar = substring(@ipAddr, @ipPos, 1)
        if @ipChar = '.' begin
            set @ipNum = (256 * @ipNum) + cast(@segNum as bigint)
            set @segNum = 0
        end else 
            set @segNum = (10 * @segNum) + cast(@ipChar as int)
        set @ipPos = @ipPos + 1    
    end
    set @ipNum = (256 * @ipNum) + cast(@segNum as bigint)
    return @ipNum
end