title: Change textbox text parent from child form
body: <p>I have two forms in my program. I have a textbox and a button in both of them. when I click on button in form1, form2 is displayed using <code>showdialog();</code>
  When I type in textbox in form2 and click on the button in this form, form2 closes and focus is on form1 and the text that I type in form2 is transferred to a textbox on form1.</p>
  
  <p>How should I do this?</p>