using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlClient;
using System.Configuration;
using System.Net;

namespace IP2Area
{
    public class IP2Area
    {
        public static string GetArea(string ip)
        {
            string area = "";
            try
            {
                string conn = ConfigurationManager.ConnectionStrings["Conn_IP"].ConnectionString;
                SqlConnection connection = new SqlConnection(conn);
                connection.Open();
                string sql = "select top 1 area from tb_ip where startip_int<" + IPToInt(ip) + " and endip_int>" + IPToInt(ip) + " order by startip_int desc,endip_int asc";
                SqlCommand cmd = new SqlCommand(sql, connection);
                SqlDataReader dr = cmd.ExecuteReader();
                if (dr.HasRows)
                {
                    dr.Read();
                    area = dr["area"].ToString();
                }
                connection.Close();
            }
            catch (Exception e)
            {
            }
            return area;
        }

        public static string GetCity(string ip)
        {
            string city = "";
            try
            {
                string conn = ConfigurationManager.ConnectionStrings["Conn_IP"].ConnectionString;
                SqlConnection connection = new SqlConnection(conn);
                connection.Open();
                string sql = "select top 1 city from tb_ip where startip_int<" + IPToInt(ip) + " and endip_int>" + IPToInt(ip) + " order by startip_int desc,endip_int asc";
                SqlCommand cmd = new SqlCommand(sql, connection);
                SqlDataReader dr = cmd.ExecuteReader();
                if (dr.HasRows)
                {
                    dr.Read();
                    city = dr["city"].ToString();
                }
                connection.Close();
            }
            catch (Exception e)
            {
            }
            return city;
        }

        public static string GetProvince(string ip)
        {
            string province = "";
            try
            {
                string conn = ConfigurationManager.ConnectionStrings["Conn_IP"].ConnectionString;
                SqlConnection connection = new SqlConnection(conn);
                connection.Open();
                string sql = "select top 1 province from tb_ip where startip_int<" + IPToInt(ip) + " and endip_int>" + IPToInt(ip) + " order by startip_int desc,endip_int asc";
                SqlCommand cmd = new SqlCommand(sql, connection);
                SqlDataReader dr = cmd.ExecuteReader();
                if (dr.HasRows)
                {
                    dr.Read();
                    province = dr["province"].ToString();
                }
                connection.Close();
            }
            catch (Exception e)
            {
            }
            return province;
        }

        //將IP地址字符串轉(zhuǎn)換成等效的數(shù)字值
        public static uint IPToInt(string ip)
        {
            IPAddress IP;
            uint ipvalue = 0;
            //若為合法的IP地址，則進(jìn)行轉(zhuǎn)換
            if (IPAddress.TryParse(ip, out IP))
            {
                String[] _ip = IP.ToString().Split('.');
                for (int i = 0; i < 4; i++)
                {
                    if (i != 3)
                    {
                        ipvalue = ipvalue + (uint)System.Convert.ToUInt32(_ip[i]) << 8;
                    }
                }
                ipvalue += (uint)System.Convert.ToUInt32(_ip[3]);
            }
            return ipvalue;
        }
    }
}