Crystal report, error during runtime in VS.. error converting string to date

Question

crystal report code

*date(val(left({?@DATEFROM},4)),
val(mid({?@DATEFROM},5,2)), 
val(right({?@DATEFROM},2)))*

these set of codes are working during the preview in crystal report XI, but during the runtime in VS 2013 it outputs error. "The field name is not known, Details errorKind...Error in formula.. the field name is not known."

Are there other way I can convert string to date without error in Visual Studio?Thanks

Answer 1

从参数名称中删除@字符。