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using the linqDataSource control programmatically (dynamically)

Posted By:      Posted Date: August 21, 2010    Points: 0   Category :ASP.Net


my scenario is this: I want to use the linqDataSource control to bind data to a gridview for it's efficient built-in paging and sorting features *but* I don't want the data to be bound until the user has input various search parameters, so I need to bind the data from a button click event. Also, the search options will be somewhat complex in that there will be several optional search parameters, via various dropdowns and textboxes, so I can't just declaratively/statically setup all the WHERE parameters on the linqDataSource (at least I'm assuming I can't, or that it may result in poor performance if I do and just assign default values like the everything wildcard '%' for the cases the user doesn't use a particular search parameter). Given that brief description, here is an example of what I'm doing, but with only one WHERE parameter for simplicity, the real code will be adding anywhere from 1 to about 12 WHERE parameters depending on how the user sets the search options in the GUI.

the linqDataSource on the aspx page:

<asp:LinqDataSource ID="ldsMain" runat="server" 
        Select="new (field1, field2, field3, etc..)" 

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