stringValue = Convert.ToString(Convert.ToInt32(stringValue , 2) , 16).ToUpper();

// The first "Convert.ToString()" is converting decimal into hexadecimal

// The second "Convert.ToInt32()" is converting binary into decimal

private string hex2binary(string hexvalue){  string binaryval = "";  binaryval = Convert.ToString(Convert.ToInt32(hexvalue, 16), 2);  return binaryval;}