/// <summary>
/// Performs filtering of the data collection.
/// </summary>
/// <typeparam name="T">Type of elements in the collection to filter.</typeparam>
/// <param name="collection">Sequence of elements to filter.</param>
/// <param name="filter">Filter which apply to collection.</param>
/// <param name="sortBy">Sorting function.</param>
/// <param name="sortAscending">Sorting direction.</param>
/// <param name="startRow">Row from which start filtering.</param>
/// <param name="pageSize">Count of rows in the page.</param>
/// <returns>Collection with specific filtering rules applied.</returns>
protected IEnumerable <T> Filter <T>(
IQueryable <T> collection,
ICollectionFilter <T> filter,
Func <T, IComparable> sortBy,
bool sortAscending,
int startRow,
int pageSize)
{
collection = filter.Filter(collection);
if (sortBy == null)
{
return(collection);
}
// Perform sorting
var sortedCollection = sortAscending
? collection.OrderBy(sortBy)
: collection.OrderByDescending(sortBy);
// Perform filtering.
var pagedCollection = sortedCollection.Skip(startRow).Take(pageSize);
return(pagedCollection);
}
