title: Append text with UITextField text
body: <p>I am running Objective-C/Cocoa in Shell in Windows, not on Mac OS X.</p>
  
  <p>I want to append a string with an existing string in a text field when I click a button. I've created a button in a window, but I don't know how to append a string when I click that button.</p>
  
  <p>How can I append a string to a text field when that button is clicked?</p>