Call help file in .net window application

We want to know how to show related topic of help file when user click F1 on specific interface.

Thanks H N Mishra

From stackoverflow

• If you are using windows forms, have a look at a help provider.

  Dropping one on your form will give you a ? button in the corner which you can then wire up to each control. You can even hyperlink that into a CHM file, along with any other part that you wish to do.