How do I pass data from child of child form to parent form in C#?

Question

I am new to c#. I have the following in my project in windows forms:

Form1 with button and DataGridView.

Form2 with button.

Form3 with button and 3 text

Answer 1

You can pass owner to method Show() for new forms. Then you can get owner form from Owner property.

private void buttonOpenForm2 _Click(object sender, EventArgs e)
{
    Form2 frm2 = new Form2();
    frm2.Show(this);
}

So you can get Form1:

(Form1)frm2.Owner

and call public method of Form1 class and pass there your new data.