Transferring data from Form2 (textbox2) to Form1 (textbox1)? [duplicate]

Answer 1

in Form1:

public void SetTextboxText(String text)
{
    txtForm1.Text = text;
}

private void btnForm1_Click(object sender, EventArgs e)
{
    var frm = new Form2(this); // pass parent form (this) in constructor
    frm.Show();
}

in Form2:

Form _parentForm;

public Form2(Form form)
{
    _parentForm = form;
}

private void txtForm2_TextChanged(object sender, EventArgs e)
{
    _parentForm.SetTextboxText(txtForm2.Text); // change Form1.txtForm1.Text
}