Multi-Field formula Malformed If statement

[Lichunhuang]

 Hi, Can someone help me with my if statement below? thank you!

IF ISNULL([_CurrentField_])
THEN [_CurrentField_]

ELSEIF REGEX_Match([_CurrentField_],"[A-Z]*")

THEN "CONTAINS([" + tostring([Filter 1])+'],"' + tostring([_CurrentField_]) + '")'"

ELSE "aa"

ENDIF

[Lichunhuang]

Thank you! It works.

Thanks for everyone's effort!!

[atcodedog05]

Happy to help : ) @Lichunhuang 

Cheers and have a nice day!