applying filters 'like' clause on data returned via subsonic

Question

i have a data access layer which returns data from stored procedures. If i bind this to a gridview control in asp.net 2.0, the users then have an option of filtering on that data select list where in they can choose the conditional clause of

• like

• =

• or

• and

Once the result is returned, I do not want to hit the Db again with the filters applied.

I have an option to use .net 3.5 if the need be. i looked at this: http://weblogs.asp.net/jgaylord/archive/2006/05/31/Filter-A-GridView-After-The-Initial-Bind.aspx

and not sure of its efficiency.

Answer 1

Are you using a SqlDataSource control on the page and binding to that? if so, then you'll have to change gears and put in a manual binding step.

you might do something like storing the DataTable in ViewState or Session, then wrapping it in a DataView that contains your filter (or no filter for the intial page load). Then you just bind to the DataView.

Answer 2

SubSonic Collections have filtering capabilities built-in. You can also use LINQ filters on them. I don't have specific examples here for you, but you can basically set Where clauses on subsonic collections and run a particular method (can't remember which one as I've never used this functionality) which applies the filter to the current collection and returns a new one. From what I saw, the original collection is not modified, it just has metadata to filter it in memory.