C#

jschell wrote:

If your source for the characters are human input is human than it seems unlikely that ReadExisting() would lose anything.

jschell wrote:

ReadLine() blocks until a new line character occurs so you can't expect it to do anything immediately based on a key press unless the key causes a end of line.

serialport.Close();

ReadLine()

OriginalGriff wrote:

Instead, handle the SerialPort.DataReceived[^] event, and get the data in that using ReadExisting - you can then add the data to the textbox in the event handler

private void Start_Click (object sender, EventArgs e)
        {
            if(Start.Text == "Start")
            {
                Start.Text = "Stop";
                _SerialPort.DataReceived += new SerialDataReceivedEventHandler (Port_DataReceived);
            }
            else
            {
                Start.Text = "Start";
            }
        }

        private void Port_DataReceived (object sender, SerialDataReceivedEventArgs e)
        {
            string data = _SerialPort.ReadExisting ();
            rtbTerminal.AppendText (data);
            rtbTerminal.ScrollToCaret ();
        }

private void Start_Click (object sender, EventArgs e)
        {
            if(Start.Text == "Start")
            {
                Start.Text = "Stop";
                _SerialPort.DataReceived += new SerialDataReceivedEventHandler (Port_DataReceived);
            }
            else
            {
                Start.Text = "Start";
            }
        }

        private void Port_DataReceived (object sender, SerialDataReceivedEventArgs e)
        {
            string data = _SerialPort.ReadExisting ();

            rtbTerminal.Invoke (new EventHandler (delegate
            {
                rtbTerminal.SelectedText = string.Empty;
                rtbTerminal.AppendText (data);
                rtbTerminal.ScrollToCaret ();
            }));
        }

bool Receive_Enable = false;

public Terminal (SerialPort Serial_Port)
        {
            InitializeComponent ();
            _SerialPort = Serial_Port;
            _SerialPort.Close ();
            _SerialPort.DataReceived += new SerialDataReceivedEventHandler (Port_DataReceived);
        }

private void Start_Click (object sender, EventArgs e)
        {
            if(Start.Text == "Start")
            {
                Start.Text = "Stop";
                _SerialPort.Open ();
                Receive_Enable = true;
            }
            else
            {
                Receive_Enable = false;
                _SerialPort.Close ();
                Start.Text = "Start";
            }
        }

private void Port_DataReceived (object sender, SerialDataReceivedEventArgs e)
        {
            if(Receive_Enable)
            {
		rtbTerminal.AppendText (Convert.ToString (_SerialPort.ReadLine ()));
		rtbTerminal.ScrollToCaret ();
            }
        }

_SerialPort.ReadExisting ()

bool Receive_Enable = false;

public Terminal (SerialPort Serial_Port)
        {
            InitializeComponent ();
            _SerialPort = Serial_Port;
            _SerialPort.Open (); // **** IF IT ISN'T ALREADY OPENED BY THE CALLING CODE.
            _SerialPort.DataReceived += new SerialDataReceivedEventHandler (Port_DataReceived);
        }

private void Start_Click (object sender, EventArgs e)
        {
            if(Start.Text == "Start")
            {
                Start.Text = "Stop";
                Receive_Enable = true;
            }
            else
            {
                Receive_Enable = false;
                Start.Text = "Start";
            }
        }

private void Port_DataReceived (object sender, SerialDataReceivedEventArgs e)
        {
            if(Receive_Enable)
            {
                int bytes = _SerialPort.BytesToRead;
                byte[] data = new byte[bytes];
                _SerialPort.Read(data, 0, bytes);
                string s = System.Text.Encoding.ASCII.GetString(data);
                Console.WriteLine(s);
                rtbTerminal.AppendText(s);
                rtbTerminal.ScrollToCaret();
            }
        }

SerialPort.Close()

ReadExisting()

stream = port.BaseStream  ;
...
byte[] buffer = new byte [ port.ReadBufferSize ] ;
...
stream.Read ( buffer , 0 , buffer.Length ) ;

deebow wrote:

This user control is placed on a base form and now the form inherits this user control.

BillWoodruff wrote:

once you have put an instance of the UserControl on the "base form:" changing the design-time appearance of the UserControl would not update the appearance of the instance of the UserControl on the base form.

 B) Form that contains an instance of Usercontrol A
Class FormWhatever : UserControl

2) The form that is loaded at program start is the usercontrol.

The base control isn't loaded unless the user chooses to go into that form.