I know this might sound basic, but as a beginner, I've been confused about the following:

I have two forms, the first one is where all connections and calculations are made, and the second one is where I want to display all the results.

FORM 1, Where I call to open the second form.

private void button_Click1(object sender, EventArgs e)
        {
            Button selected = sender as Button;
            openClientForm(new Form2());
        }

private Form activeForm = null;
        private void openClientForm( Form clientForm)
        {
            if (activeForm != null)
                activeForm.Close();
            activeForm = clientForm;
            clientForm.TopLevel = false;
            clientForm.FormBorderStyle = FormBorderStyle.None;
            clientForm.Dock = DockStyle.Fill;
            panelClientForm.Controls.Add(clientForm);
            panelClientForm.Tag = clientForm;
            clientForm.BringToFront();
            clientForm.Show();
        }

FORM 2)

public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
            //Form2_Load();
            updateText(txtCmdConsole, Form1.cmdres);
        }



        private void updateText(TextBox text, string strdata)
        {
            text.AppendText(strdata);

        }
    }

I have 1 question.

1. When I open the second form, How can I run the Method updateText from form 1 and display the result in the second form? The reason I ask is that form1 should still be running in the background, and if a certain condition is met, I want the update text to be run in form 1(to get values from there) and update the second form.

CodePudding user response：

First, your activeForm should be of type Form2, not just Form, otherwise you cannot call specific methods from it (at least not easily). The code should look like this:

    private Form2 activeForm = null;
    private void openClientForm(Form2 clientForm)
    {
        if (activeForm != null)
            activeForm.Close();
        activeForm = clientForm;

    //...

Form2 can then offer a public interface to update certain text from the outside, with methods which don't expect internal controls as parameters. Something along the lines of

    // inside Form2
    public void UpdateCmdText(string strdata)
    {
        updateText(txtCmdConsole, strdata);
    }

Now you can call this method inside Form1 whereever you like:

    activeForm.UpdateCmdText(someNewResult)

Hope this helps.