context-sensitive help

[Erich Ruth]

I have a dialog box with 2 edit boxes for data entry. How can I implement a command, like ctrl-H, so that when the user has the cursor in edit box 1 and does ctrl-H that a dialog box pops-up with text explaining this edit box, and when the cursor is in edit box 2 and the user does ctrl-H that a different dialog box pops-up with text explaining this other edit box.

Any response any one can give me will be greatly appreciated.