public static byte GetByte(object o)
{
byte retInt = 0;
if (o != null)
{
byte tmp;
if (byte.TryParse(o.ToString().Trim(), out tmp))
{
retInt = tmp;
}
}
return retInt;
} 

public static byte GetByteFormHex(string hexValue)
{
try
{
return Convert.ToByte(hexValue, 16);
}
catch 
{
return 0;
}
}

public static byte GetByteFormSingleString(string value)
{
return GetByteFormChar(Convert.ToChar(value));
}

public static byte[] GetBytes(string values)
{
return System.Text.Encoding.Default.GetBytes(values);
}