How to handle dynamic GUIs in .net

Question

I've come across a problem, that is probably seen pretty often, but has never really been discussed here.

In my Gui, I'm adding Controls in a for loop to a Flowpanellayout. The point is to display "reports" from a database. It has to be dynamic, because the number of reports can be different from day to day.

---

Pseudocode Adding Gui Elements:

for(int i = 0; i < reports.Count; i++)
{
    TextBox textboxPerson = new TextBox();
    textboxPerson.Name = "TextboxName" + i;
    textboxPerson.Text = reports[i].Name;
    textboxPerson.TextChanged += new EventHandler(this.textboxPerson_TxtChanged);

    Label labelToChange = new Label();
    labelToChange.Name = "label"+i;
    labelToChange.Text = "";

    flowlayoutPanel.Controls.Add(textboxPerson);
    flowlayoutPanel.Controls.Add(labelToChange);
}

Event Handler:

private void textboxPerson_TextChanged(object sender, EventArgs e)
{
   //So far, I'm only getting the number of the Textbox that changed.
}

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Here is, where I need your advise. The Textboxs and Labels are matching (iE, Texbox1 is as you can see connected to Label1). But how do I address one Control in particular?

• If Texbox1's Text changes, how do I address Label1 to change its Text or something?
• Is there a state of the art of adding dynamic Gui Elements to a Form and handling them?

Answer 1

You can use the Tag property of the controls, for instance. In your loop, you can assign the Label to the Tag property of the TextBox like this:

TextBox textboxPerson = new TextBox();
// do the stuff with the text box

Label labelToChange = new Label();
// do the stuff with the label
textboxPerson.Tag = labelToChange

Then you can get to the Label in the TextChanged event of the TextBox:

private void textboxPerson_TextChanged(object sender, EventArgs e)
{
   //So far, I'm only getting the number of the Textbox that changed.
   Label theLabel = (sender as TextBox).Tag;
   theLabel.Text = "whatever should go here";
}