I'm not sure i understand your question. Please post the code and the error you're recieving...
but I think you're saying one of two things
1) Decimal.Parse doesn't work from within the switch () statement
I'm not sure that you can call a fnc from insinde the switch( ) statement. If you can not, then parse to decimal on the line before, then just dump the new decimal into the switch statement
the other thing i think you might be saying is that you can not use a decimal in a switch statement, and I have never tried to do that (i'm not sure a switch statement is really a good design choice if your working with decimals.) you may want to look into a series of if statements that may work better with decimals... post back to let me know if that helped, if not, give more specifics about your question...
switch statement has no support for decimal:
arse method?

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