C#

public String ConvertToBase(int num, int nbase)
        {
            String chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";

            // check if we can convert to another base
            if (nbase < 2 || nbase > chars.Length)
                return "";

            int r;
            String newNumber = "";

            // in r we have the offset of the char that was converted to the new base
            while (num >= nbase)
            {
                r = num % nbase;
                newNumber = chars[r] + newNumber;
                num = num / nbase;
            }
            // the last number to convert
            newNumber = chars[num] + newNumber;

            return newNumber;
        }

const string chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
static readonly int num_chars = chars.Length;

static string NumberToCode(int number)
{
  if (number < 0 || number > num_chars * num_chars)
    throw new ArgumentOutOfRangeException();

  return chars[number / num_chars].ToString() + chars[number % num_chars];
}

static public string EncodeTo64(string toEncode)
{
    byte[] toEncodeAsBytes = System.Text.ASCIIEncoding.ASCII.GetBytes(toEncode);
    string returnValue = System.Convert.ToBase64String(toEncodeAsBytes);
    return returnValue;
}

static public string DecodeFrom64(string encodedData)
{
    byte[] encodedDataAsBytes = System.Convert.FromBase64String(encodedData);
    string returnValue = System.Text.ASCIIEncoding.ASCII.GetString(encodedDataAsBytes);
    return returnValue;
}

Collin Jasnoch wrote:

its "a module"

Luc Pattyn wrote:

exactly what I needed

using System;
using System.Web;
using System.Xml;
 

/// 
/// HTTP module to restrict access by IP address
/// 
public class SecurityHttpModule : IHttpModule
{
public SecurityHttpModule() { }
/// 
/// Module are initialize here by using public Init function, that does not return a value;
/// HttpApplication: defines the methode properties and events that are common to all application object;
/// 
/// 
public void Init(HttpApplication context)
{
context.BeginRequest += new EventHandler(Application_BeginRequest);
}
/// 
/// 
/// 
/// 
/// 
private void Application_BeginRequest(object source, EventArgs e)
{
HttpContext context = ((HttpApplication)source).Context;
string ipAddress = context.Request.UserHostAddress;
//string ipAddress = "202.183.79.250";//ok ip for test
//string ipAddress = "202.183.64.0";//ok ip for test
// string st="";
// string st1 = "";
string strIPAddress = context.Request.ServerVariables["HTTP_X_FORWARDED_FOR"];
if (strIPAddress == null || strIPAddress == "")
{
//string[] myservab = context.Request.ServerVariables.AllKeys;
//for (int i = 0; i <= myservab.Length; i++)
//{
// //respons.Write("Key: " + myservab[i] + "
");

// st += " Key: " + myservab[i] + " 
" ;
// string[] myservab2 = context.Request.ServerVariables.GetValues(myservab[i]);
// for (int j = 0; j < myservab2.Length; j++)
// {
// st1 += "Key : " + myservab[i] + " Value : " + myservab2[j] + "
";
// //Response.Write("Value " + myservab2 + ": " + Server.HtmlEncode(myservab2[j]) + "
");
// }
 
//}
strIPAddress = context.Request.ServerVariables["REMOTE_ADDR"].ToString();
}
if (!IsValidIpAddress(ipAddress))
{
context.Response.StatusCode = 403; // (Forbidden)
}
else
{
string filePath = context.Request.FilePath;
string fileExtension =
VirtualPathUtility.GetExtension(filePath);
if (fileExtension.Equals(".aspx"))
{
context.Response.Write("
" +
"HelloWorldModule: Beginning of Request" +
"

--------------------------------------------------------------------------------
");
}
}
}
 
private bool IsValidIpAddress(string ipAddress)
{
 
double myipnom = IPAddressToNumber(ipAddress);
//long myipnom = ip2ipno(ipAddress);
// long myipra = 3401007104;
string myip = ipno2ipaddress(myipnom);
bool sta = false;
Class1 obj = new Class1();
XmlDocument xmldoc = obj.getdata(myipnom);
//xmldoc.InnerXml
// XmlNodeList xmlist = xmldoc.SelectNodes("CountryIps[@*]");
XmlNodeList xmlist = xmldoc.GetElementsByTagName("CountryIps");
 
// XmlNodeList xmlist = xmldoc.InnerXml("NewDataSet[@*]");
//XmlNodeList xmll=xmldoc.InnerXml
 
foreach (XmlNode nl in xmlist)
{
if (nl != null)
{
// XmlNode tablexml = nl.SelectSingleNode("id");
string ipFrom = nl["ipFROM"].InnerXml;
string ipTo = nl["ipTO"].InnerXml;
string countrySHORT = nl["countrySHORT"].InnerXml;
string countryLONG = nl["countryLONG"].InnerXml;
bool conf;
if (ipFrom != null && ipTo != null)
{
conf = IsInRange(myipnom, double.Parse(ipFrom), double.Parse(ipTo));
if (conf == true && countrySHORT=="IN")
{
sta = true;
}
else { sta = false; }
}
}
else
{
sta = false;
}
 
}
return sta;
// return (ipAddress == "127.0.0.1");
}
public bool IsInRange(double ipNo, double ipFrom, double ipTo)
{
Int64 ipf= Convert.ToInt64(ipFrom);
Int64 ipn = Convert.ToInt64(ipNo);
Int64 ipt = Convert.ToInt64(ipTo);
return ipn >= ipf && ipn <= ipt;
}
public long ip2ipno(string ipAddress)
{
char[] splitchar = { '.' };
string[] strary = ipAddress.Split(splitchar);
long ipNo;
double ipno1;
double ipNumber, ipNumber1, ipNumber2, ipNumber3;
ipNumber = (Math.Pow(2, 24) * int.Parse(strary[0]));
ipNumber1 = (Math.Pow(2, 16) * int.Parse(strary[1]));
ipNumber2 = (Math.Pow(2, 8) * int.Parse(strary[2]));
ipNumber3 = int.Parse(strary[3]);
ipno1 = (ipNumber + ipNumber1+ ipNumber2 + ipNumber3);
ipNo = (Convert.ToInt64(ipNumber) + Convert.ToInt64( ipNumber1 )+ Convert.ToInt32( ipNumber2 )+ Convert.ToInt32(ipNumber3));
return ipNo;
}
public double IPAddressToNumber(string IPaddress)
{
int i;
string[] arrDec;
double num = 0;
if (IPaddress == "")
{
return 0;
}
else
{
arrDec = IPaddress.Split('.');
for (i = arrDec.Length - 1; i >= 0; i = i - 1)
{
num += ((int.Parse(arrDec[i]) % 256) * Math.Pow(256, (3 - i)));
}
return num;
}
}
 
public string ipno2ipaddress(double ipNo)
{
double w, x, y, z;
w = (ipNo / 16777216) % 256;
x = (ipNo / 65536) % 256;
y = (ipNo / 256) % 256;
z = (ipNo) % 256;
int w1 = Convert.ToInt16(Math.Floor(w));
int x1 = Convert.ToInt16(Math.Floor(x));
int y1 = Convert.ToInt16(Math.Floor(y));
int z1 = Convert.ToInt16(Math.Floor(z));
//int w1 = Math.Floor(w);
return (w1)+ "." + Convert.ToInt32(x1) + "." + Convert.ToInt32(y1) + "." + Convert.ToInt32(z1);
}
public void Dispose() { /* clean up */ }
 
}
 
//XmlDocument xml = new XmlDocument();
//xml.LoadXml(myXmlString); //myXmlString is the xml file in string //copying xml to string: string myXmlString = xmldoc.OuterXml.ToString();
//XmlNodeList xnList = xml.SelectNodes("/Element[@*]/ANode/BNode/CNode");
//foreach (XmlNode xn in xnList)
//{
// XmlNode example = xn.SelectSingleNode("Example");
// if (example != null)
// {
// string na = example["Name"].InnerText;
// string no = example["NO"].InnerText;
// }
//}