I think you'll need to use the macro symbol for that. Its an ampersand (&)
Place it before a variable and use a dot or a space to terminate it.
ie, this.&lccontrol..value
Most likely you'll end up with
replace &curfield with eval("b." + field)

This stuff is pretty well documented in help, but there is also a thread running around here wherein someone posted an EXECELLANT description of how naming and macro conventions work. He was going to write it up as a KB or a FAQ article, don't know if that was done yet. Maybe someone saved it and can email it to you, or tell you the thread number.

>The Evaluate function worked fine for comparing the two values. It will also allow me to replace with the Evaluate() of that string as well. But I still need to know how to reference the field that I am trying to replace.