//This constructor stores filtering route segments, as well as
//the paging and sorting route segments stored by the base constructor
public BooksGridBuilder(ISession sess, BookGridDTO values, string defaultSortFilter) : base(sess, values, defaultSortFilter)
{
//store filter route segments - add filter prefixes if this is inital load
//of page with default values rather than route values (route values have prefix)
bool isInitial = values.Genre.IndexOf(FilterPrefix.Genre) == -1;
Routes.AuthorFilter = (isInitial) ? FilterPrefix.Author + values.Author : values.Author;
Routes.GenreFilter = (isInitial) ? FilterPrefix.Genre + values.Genre : values.Genre;
Routes.PriceFilter = (isInitial) ? FilterPrefix.Price + values.Price : values.Price;
SaveRouteSegment();
}
//DTO has properties for the paging, soreting, and filtering route segments defined in teh Startup.cs file
public ViewResult List(BookGridDTO values)
{
//get grid builder, which loads route segment values and stores them in session
var builder = new BooksGridBuilder(HttpContext.Session, values, defaultSortFilter: nameof(Book.Title));
//create a BookQueryOPtions object to build a query expresssion for a page of data
var options = new BookQueryOptions
{
Includes = "BookAuthors.Author, Genre",
OrderByDirection = builder.CurrentRoute.SortDirection,
PageNumber = builder.CurrentRoute.PageNumber,
PageSize = builder.CurrentRoute.PageSize
};
//call the SortFilter() method of the BookQueryOPtions object and pass it to the builder
//object. It uses the route information and the properties of the builder object to
//add sort and filter options to the query expression.
options.SortFilter(builder);
//create view model and add page of book data, data for drop-downs,
//the current route, and the total number of pages.
var vm = new BookListViewModel
{
Books = data.Books.List(options),
Authors = data.Authors.List(new QueryOptions <Author> {
OrderBy = a => a.FirstName
}),
Genres = data.Genres.List(new QueryOptions <Genre> {
OrderBy = g => g.Name
}),
CurrentRoute = builder.CurrentRoute,
TotalPages = builder.GetTotalPages(data.Books.Count)
};
return(View(vm));
}
