What is the best way to change BackColor in a textbox, editbox or combobox, listbox based upon the box being empty or not.

For example I have a textbox with a white background, if the user fails to enter a value in the textbox I want to change the background color to pale yellow. If the user enters a value I want to change the background color to white.

If the user goes back to that same textbox I want to change background color back to pale yellow if the value is removed.

In other words, make the background color of all boxes pale yellow if not filled out and white if filled out. So at a glance you can see what fields and what fields have not been completed on a form.

Thanks for the help. I have tried several different ways and some work, but I want to know if there might be a better way. Right now, I have background color changing code inside every object and there are many objects on my forms. Would it be better to do it at the form lever or the object level. And would it be better to do it at Refresh or Init or Interactive Change?

All the best,
Steve Kramer
Kramer & Kramer Design