How to read data from serial port on Raspberry Pi+MonoDevelop?

i installed MonoDevelop on raspberry pi. my send data code is:

try
    {

        SerialPort myport = new  SerialPort("/dev/ttyAMA0", 9600, Parity.None, 8, StopBits.One);
    myport.Open ();

        myport.WriteLine("this is Test");
        myport.Close();
    }
    catch (Exception ex)
    {
        label1.Text = ex.Message.ToString ();
    }

how i can read data from serial port in raspberry pi and mono? please help me, Thank's