One of my customers wanted to highlight all of the empty values in a string column, but still leave the highlighted space empty. I tried using a background color formula but that didn’t work. Then I remembered an article I wrote about display strings  and how you can’t force a display string to show anything when a field was empty. It seems the same thing is true about background colors.

I tried using IsNull, converting nulls to default values and even the highlight expert. The only thing that worked was to replace the field with a formula like this:

If {Table.Field} = ''
then ' ' //single space
else {Table.Field}

The second line isn’t an empty string but is a single space. Because a space is a character, Crystal will format it with a background color.