Encryption and Decryption in C#

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

///

/// Summary description for EncryptionDecryption
///

public class EncryptionDecryption
{

//Encription
public string base64Encode(string sData)
{
try
{
byte[] encData_byte = new byte[sData.Length];

encData_byte = System.Text.Encoding.UTF8.GetBytes(sData);

string encodedData = Convert.ToBase64String(encData_byte);

return encodedData;

}
catch (Exception ex)
{
throw new Exception("Error in base64Encode" + ex.Message);
}
}


// Decryption
public string base64Decode(string sData)
{

System.Text.UTF8Encoding encoder = new System.Text.UTF8Encoding();

System.Text.Decoder utf8Decode = encoder.GetDecoder();

byte[] todecode_byte = Convert.FromBase64String(sData);

int charCount = utf8Decode.GetCharCount(todecode_byte, 0, todecode_byte.Length);

char[] decoded_char = new char[charCount];

utf8Decode.GetChars(todecode_byte, 0, todecode_byte.Length, decoded_char, 0);

string result = new String(decoded_char);

return result;

}

}