public static string readEPCLabel(string strEPC, out ulong uEPCNumber)
{
try
{
string EPClabel = RFIDTagInfo.HEXToASCII(strEPC.Substring(0, 6).ToUpper());
string serialNumber = strEPC.Substring(7).Replace(" ", "");
uEPCNumber = ulong.Parse(serialNumber);
string EPSnumber = uEPCNumber.ToString("D20");
return(EPClabel + EPSnumber);;
}
catch (Exception exp)
{
Trace.WriteLine("Get Exception " + exp.Message);
uEPCNumber = 0;
return("");
}
}
public string DecryptFromHEX(string inputPart1, string inputPart2)
{
// Create AesManaged
if (aes.Key == null || inputPart2 == "")
{//can't covert 0x00 to ASCII word
return("");
}
for (int j = 0; j < inputPart2.Length / 6; j++)
{
int pos = inputPart2.LastIndexOf("00");
if (pos != -1)
{
inputPart2 = inputPart2.Remove(pos - 3);
}
else
{
break;
}
}
for (int i = 0; i < 2; i++)
{
string hex2Ascii = "";
string plaintext = "";
try
{
switch (decState)
{
case decryptedState.CombinedMemory:
{
hex2Ascii = RFIDTagInfo.HEXToASCII(
inputPart1 + inputPart2);
if (!IsBase64String(hex2Ascii))
{
//Trace.WriteLine("Format not support1 " + hex2Ascii);
decState = decryptedState.SingleMemroy;
continue;
}
}
break;
case decryptedState.SingleMemroy:
{
hex2Ascii = RFIDTagInfo.HEXToASCII(inputPart2);
if (!IsBase64String(hex2Ascii))
{
//Trace.WriteLine("Format not support2 " + inputPart2);
decState = decryptedState.CombinedMemory;
return("");
}
}
break;
}
//Trace.WriteLine("Read encrypted message " + hex2Ascii +
// ", decState = " + decState.ToString());
byte[] cipherText = System.Convert.FromBase64String(hex2Ascii);
plaintext = DecryptData(cipherText);
if (plaintext != "")
{
decState = decryptedState.CombinedMemory;
return(plaintext);
}
}
catch (Exception exp) { }
switch (decState)
{
case decryptedState.CombinedMemory:
decState = decryptedState.SingleMemroy;
break;
case decryptedState.SingleMemroy:
decState = decryptedState.CombinedMemory;
return("");
}
}
return("");
}
