title: Winforms performance issue with Numeric up down and list box
body: <p>In my Win forms app, i have a Numeric up down and a list box. 
  when i increase/change value in numeric up down, that many rows are added in list box.</p>
  
  <p>for ex. when i have value '1' in my numeric up down and i change the value to a larger number say '300', it adds 300 lines in the list box but it takes hell lot of time to do it.</p>
  
  <p>is there any way by which i can reduce this time.
  any help would be appreciated. thanks. </p>