I am using a filter control in conjunction with a grid. The columns available in the grid change depending on user preferences. When a string column is selected in the filter control; two of the options available are 'Value Exists' and 'No Value Exists'. The expressions generated by these options are [ColumnName] != null and [ColumnName] == null. Is it possible to override this behavior such that an empty string would NOT be considered a value.
ie.
Value Exists => Any value that is not null or empty
No Value Exists => Any null or empty value.
ie.
Value Exists => Any value that is not null or empty
No Value Exists => Any null or empty value.