private static IQueryable <T> Filter <T>(IQueryable <T> queryable, KendoFilter filter)
{
if (filter != null && filter.Logic != null)
{
// Collect a flat list of all filters
var filters = filter.All();
// Get all filter values as array (needed by the Where method of Dynamic Linq)
var values = filters.Select(f => f.Value).ToArray();
// Create a predicate expression e.g. Field1 = @0 And Field2 > @1
string predicate = filter.ToExpression(filters);
// Use the Where method of Dynamic Linq to filter the data
queryable = queryable.Where(predicate, values);
}
return(queryable);
}
/// <summary>
/// Applies data processing (paging, sorting and filtering) over IQueryable using Dynamic Linq.
/// </summary>
/// <typeparam name="T">The type of the IQueryable.</typeparam>
/// <param name="queryable">The IQueryable which should be processed.</param>
/// <param name="take">Specifies how many items to take. Configurable via the pageSize setting of the Kendo DataSource.</param>
/// <param name="skip">Specifies how many items to skip.</param>
/// <param name="sort">Specifies the current sort order.</param>
/// <param name="filter">Specifies the current filter.</param>
/// <returns>A DataSourceResult object populated from the processed IQueryable.</returns>
public static KendoDataSourceResult ToDataSourceResult <T>(this IQueryable <T> queryable, int take, int skip, IEnumerable <KendoSort> sort, KendoFilter filter)
{
return(queryable.ToDataSourceResult(take, skip, sort, filter, null));
}
/// <summary>
/// Applies data processing (paging, sorting, filtering and aggregates) over IQueryable using Dynamic Linq.
/// </summary>
/// <typeparam name="T">The type of the IQueryable.</typeparam>
/// <param name="queryable">The IQueryable which should be processed.</param>
/// <param name="take">Specifies how many items to take. Configurable via the pageSize setting of the Kendo DataSource.</param>
/// <param name="skip">Specifies how many items to skip.</param>
/// <param name="sort">Specifies the current sort order.</param>
/// <param name="filter">Specifies the current filter.</param>
/// <param name="aggregates">Specifies the current aggregates.</param>
/// <returns>A DataSourceResult object populated from the processed IQueryable.</returns>
public static KendoDataSourceResult ToDataSourceResult <T>(this IQueryable <T> queryable, int take, int skip, IEnumerable <KendoSort> sort, KendoFilter filter, IEnumerable <KendoAggregator> aggregates)
{
// Filter the data first
queryable = Filter(queryable, filter);
// Calculate the total number of records (needed for paging)
var total = queryable.Count();
// Calculate the aggregates
var aggregate = Aggregate(queryable, aggregates);
// Sort the data
queryable = Sort(queryable, sort);
// Finally page the data
if (take > 0)
{
queryable = Page(queryable, take, skip);
}
return(new KendoDataSourceResult
{
Data = queryable.ToList(),
Total = total,
Aggregates = aggregate
});
}
