Hi,
 
I've just started learning to use fields within AutoCAD drawings, but I've hit a bit of a speedbump. I'm creating a master drawing with a dimension containing a text override (as this part of the drawing is purely a schematic, and isn't to scale).  The thing is, this text override may contain either a string saying "See Front Sheet" or a numerical value.  In order to use this in a formula, I need the text to be evaluated as 0 in the former case, as my formula-based fields are currently evaluating as "####" when a string is entered.
 
For example, one of the fields will add 127 to the value entered in the text override.  If the user enters 1000, I'd want it to display 1127, whereas if the user entered "See Front Sheet", I'd need it to display 127.
 
Thanks,
Lee.