Receiving data from COM3 port gives error?

Question

I am trying to read and write data on serial port (COM3) and my write method works well but read method doesn't ,I showed my code below please have a look their and correct me if i am going wrong.

Thanks.

 

 

public partial class Form1 : Form

{

private SerialPort port = new SerialPort("COM3");

public Form1()

{

InitializeComponent();

}

public void port_DataReceived(object sender, SerialDataReceivedEventArgs e)

{

string indata = port.ReadExisting();

textBox1.Text = indata;

}

private void Enable_Click(object sender, EventArgs e)// enable button

{

port.BaudRate = 9600;

port.Open();

if (port.IsOpen)

{

Enable.Enabled = false;

Disable.Enabled = true;

}

}

private void Disable_Click(object sender, EventArgs e) // disable button

{

if (port.IsOpen)

{

port.Close();

Enable.Enabled = true;

Disable.Enabled = false;

}

}

private void button1_Click(object sender, EventArgs e) // send button

{

try

{

string strToSend;

strToSend = textBox2.Text;

if (port.IsOpen)

{

port.Write(strToSend);

port.Close();

}

else

{

port.Open();

port.Write(strToSend);

port.Close();

}

}

catch(Exception es) { MessageBox.Show(es.Message); }

}

private void button2_Click(object sender, EventArgs e) //receive button

{

try

{

port.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived);

port.Open();

Application.Run();

}

catch (Exception es) { MessageBox.Show(es.Message); }

}

}