3.0 KiB
Now when you submit a search, the URL contains the search query string. Searching will also go to the HttpGet Index action method, even if you have a HttpPost Index method.
The following markup shows the change to the form tag:
<form asp-controller="Movies" asp-action="Index" method="get">
Adding Search by genre
Add the following MovieGenreViewModel class to the Models folder:
[!code-csharpMain]
The movie-genre view model will contain:
- A list of movies.
- A
SelectListcontaining the list of genres. This will allow the user to select a genre from the list. movieGenre, which contains the selected genre.
Replace the Index method in MoviesController.cs with the following code:
[!code-csharpMain]
The following code is a LINQ query that retrieves all the genres from the database.
[!code-csharpMain]
The SelectList of genres is created by projecting the distinct genres (we don't want our select list to have duplicate genres).
movieGenreVM.genres = new SelectList(await genreQuery.Distinct().ToListAsync())
Adding search by genre to the Index view
Update Index.cshtml as follows:
[!code-HTMLMain]
Examine the lambda expression used in the following HTML Helper:
@Html.DisplayNameFor(model => model.movies[0].Title)
In the preceding code, the DisplayNameFor HTML Helper inspects the Title property referenced in the lambda expression to determine the display name. Since the lambda expression is inspected rather than evaluated, you don't receive an access violation when model, model.movies, or model.movies[0] are null or empty. When the lambda expression is evaluated (for example, @Html.DisplayFor(modelItem => item.Title)), the model's property values are evaluated.
Test the app by searching by genre, by movie title, and by both.