public string readCard()
{
StringBuilder str = new StringBuilder();
int au = E7Lib.fw_authentication(iDevice, 0, sectorNumber);
int result = E7Lib.fw_read_hex(iDevice, sectorNumber * 4,
str);
if (str.Length > 32)
{
str = str.Remove(32, 1);
}
if (0 == result)
{
return(HexToStr(str.ToString()));
}
else
{
return("");
}
}