encrypt and decrypt query string

[hanusoftware]

This code has been used to encrypt and decrypt query string .No matter what the lenght of the url is ,this code will encrypt the key and the value the query string into 25 digit






using System;
using System.Collections.Generic;
using System.Text;
using System.Collections.Specialized;
using System.Collections;
using System.Web;



namespace BusinessLayer
{
public class QueryString : NameValueCollection
{
private string document;
public string Document
{
get
{
return document;
}
}
public QueryString()
{
}
public QueryString(NameValueCollection clone): base(clone)
{
}
//################################################## ###############################################
//This Class Has been used to get the URl from the address browser of the page
//################################################## ###############################################
//this method has been used to get the current URL of the page
public static QueryString FromCurrent()
{

//returns the current url from the address bar
return FromUrl(HttpContext.Current.Request.Url.AbsoluteUr i);

}
/// <summary>
/// This method has been used to divide the Address URl into characters chunks
/// </summary>
/// <param name="url"></param>
/// <returns></returns>
public static QueryString FromUrl(string url)
{
//it breaks the address URL in array with separator of ? mark
//this line breaks the Querystring and page
string[] parts = url.Split("?".ToCharArray());
//instantiate the class object
QueryString qs = new QueryString();
//assign the page address to the variable
qs.document = parts[0];
//if there is any data in array
if (parts.Length == 1)
return qs;
//breaks the QueryString into characters chunks with separator mark &
string[] keys = parts[1].Split("&".ToCharArray());
foreach (string key in keys)
{
//again breaks into chunks by + mark
string[] part = key.Split("=".ToCharArray());
if (part.Length == 1)
qs.Add(part[0], "");
//adds the QueryString key and value pair to the assigned variable
qs.Add(part[0], part[1]);
}
return qs;


}
/// <summary>
/// This method clear all exceptions in the passed string
/// </summary>
/// <param name="except"></param>
public void ClearAllExcept(string except)
{
//calls the method to clear except
ClearAllExcept(new string[] { except });

}
/// <summary>
/// this is the usual method which has to call clear all exceptions
/// </summary>
/// <param name="except"></param>
public void ClearAllExcept(string[] except)
{
//take an arrayList
ArrayList toRemove = new ArrayList();
foreach (string s in this.AllKeys)
{
foreach (string e in except)
{
if (s.ToLower() == e.ToLower())
if(!toRemove.Contains(s))
toRemove.Add(s);

}
}
foreach (string s in toRemove)
this.Remove(s);
}
/// <summary>
/// this method adds the key value pairs in QueryString of the URL
/// </summary>
/// <param name="name"></param>
/// <param name="value"></param>
public override void Add(string name, string value)
{
//checks nullability of the name
if (this[name] != null)
//if not null then assign value to it
this[name] = value;

else

base.Add(name, value);

}



public override string ToString()
{

return ToString(false);

}


/// <summary>
/// this ethod has been used to join all the characters array to the URL
/// </summary>
/// <param name="includeUrl"></param>
/// <returns></returns>
public string ToString(bool includeUrl)
{

string[] parts = new string[this.Count];

string[] keys = this.AllKeys;
//for each keys breaks the URL into chunks
for (int i = 0; i < keys.Length; i++)

parts[i] = keys[i] + "=" + HttpContext.Current.Server.UrlEncode(this[keys[i]]);

string url = String.Join("&", parts);

if ((url != null || url != String.Empty) && !url.StartsWith("?"))

url = "?" + url;

if (includeUrl)

url = this.document + url;

return url;

}

}

}

[guitarman]

what is the purpose of this class? is it based on .net?

I.e. could you give a real time example? (not everyone has the c# compiler)

[Singachea]