lamba / predicate from grid filters ?

[scott]

I have a gridview with ItemsSource set to a DataTable ... I want to get the results of filtering without actually doing the filtering ... Something like:

IENumberable<DataRow> list = from rows in Grid.ItemsSource select rows;
var newList = rows.Where(Grid.FilterDescriptors);
foreach (DataRow dr in newList)
    // Do Something

In this post: http://www.telerik.com/community/forums/aspnet-mvc/grid/grid-and-nhibernate-linq.aspx the reply from Atanas leads me to believe its easy to do ?   "You can check the implementation of the Where extension method. There is some code which builds a LambdaExpression from the filter descriptors:"

Thank you -
Scott

[Vlad]

Hello,

 You can use the grid Items to get actual grid items after filter. 

Regards,
Vlad
the Telerik team

[scott]

Hi Vlad.   But I want to re-use the filters via LINQ as shown and described ... Can I do this with DataTable rows ?

---------

Hi Carson Wilkins,

You can check the implementation of the Where extension method. There is some code which builds a LambdaExpression from the filter descriptors:

public static IQueryable Where(this IQueryable source, IEnumerable<IFilterDescriptor> filterDescriptors)
        {
            if (filterDescriptors.Count() > 0)
            {
                var parameterExpression = Expression.Parameter(source.ElementType, "item");

                var expressionBuilder = new FilterDescriptorCollectionExpressionBuilder(parameterExpression, filterDescriptors);
                var predicate = expressionBuilder.CreateFilterExpression();
                return source.Where(predicate);
            }

            return source;
        }

Kind regards,
Atanas Korchev
the Telerik team

-----------

Thank you -
Scott

[Vlad]

Hello scott,

 There will be no problem to do this however our extension method is for IQueryable - you need to call AsQueryable():

var rows = table.Rows.AsQueryable().Where(RadGridView1.FilterDescriptors);

Kind regards,
Vlad
the Telerik team