try
Result:=Cnn.Execute('SELECT MAX(AutoId) FROM Art').Fields[0].Value;
except
on E:EVariantTypeCastError do Result:=0;
end;
Result:=Cnn.Execute('SELECT MAX(AutoId) FROM Art').Fields[0].Value;
except
on E:EVariantTypeCastError do Result:=0;
end;
except
在这写异常的提示就可以了。
end;