Question

I am working with some electronics instruments using GPIB. I can communicate with instruments like this:

K2400.WriteString("*IDN?", true);
textBoxK2400.Text += K2400.ReadString() + Environment.NewLine;

The first line will execute a command, and in the second line I add the response of the last command to the textbox. How can I write the command in the textbox directly and add the response?

For example, if the user command entered after an indicator like “>>” and hitting ENTER, the response should be added in the next line of textbox.

So how can I read the last line of a textbox and add the respone in a new line? I am looking for a method like:

private void Execute(string command)
{
  K2400.WriteString(command, true);
  textBoxK2400.Text += K2400.ReadString() + Environment.NewLine;
}

Answer 1

You could try this:

private void textBoxK2400_KeyDown(object sender, KeyEventArgs e)
{
    if (e.KeyCode == Keys.Return)
    {
        string command = textBoxK2400.Text.Split('\n').LastOrDefault();
        if (!String.IsNullOrEmpty(command) && command.StartsWith(">>"))
        {
            K2400.WriteString(command.Substring(2), true);
            textBoxK2400.Text += K2400.ReadString() + Environment.NewLine;
            textBoxK2400.Text += ">>"; // It's not necessary
        }
    }
}