private void SelectCategoriesButton_Click(object sender, EventArgs e)
{
var categories = CategoryCheckedListBox.CheckedCategoriesList().Select(category => (int?)category.CategoryID);
var ops = new DataOperations();
var data = ops.ProductsByCategories(categories.ToList()).ToList();
ProductDataGridView.DataSource = data;
ProductDataGridView.ExpandColumns();
}
/// <summary>
/// Read all categories without the change tracker
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private async void MainForm_Shown(object sender, EventArgs e)
{
using (var context = new NorthWindContext())
{
await Task.Run(async() =>
{
var categories = await context.Categories.AsNoTracking().ToListAsync();
CategoryCheckedListBox.InvokeIfRequired(clb => clb.DataSource = categories);
});
}
GetSelectedButton.Enabled = true;
}
private async void GetSelectedButton_Click(object sender, EventArgs e)
{
ResultsTextBox.Text = "";
var sb = new StringBuilder();
/*
* Get all checked categories primary key in the checked list box
*/
var indices = CategoryCheckedListBox.SelectedCategoryIdentifier();
if (indices.Length <= 0)
{
return;
}
using (var context = new NorthWindContext())
{
/*
* Get all products for each category, not FindAllAsync expects an
* object array not an int array so they are converted via
* Array.ConvertAll.
*/
Categories[] categories = await context.FindAllAsync <Categories>(Array.ConvertAll(indices, id => (object)id));
/*
* Display in a text box
*/
foreach (Categories category in categories)
{
sb.AppendLine(category.CategoryName);
List <Products> products = context.Products
.AsNoTracking().Where(prod => prod.CategoryId == category.CategoryId)
.ToList();
foreach (Products product in products)
{
sb.AppendLine($" {product.ProductId,-4}{product.ProductName}");
}
sb.AppendLine();
}
ResultsTextBox.Text = sb.ToString();
}
}
/// <summary>
/// Populates input fields with data of the selected item in the list view.
/// </summary>
private void RecipesListView_SelectedIndexChanged(object sender, EventArgs e)
{
if (RecipesListView.SelectedItems.Count != 0)
{
// get the selected item
var selectedRecipe = RecipesListView.SelectedItems[0]; // multiselect is disabled. there is only one selected item
// populate inputs
RecipeTitleTextBox.Text = selectedRecipe.SubItems[0].Text;
TimeNumericUpDown.Value = int.Parse(selectedRecipe.SubItems[1].Text);
DifficultyComboBox.SelectedItem = selectedRecipe.SubItems[2].Text;
CategoryCheckedListBox.ClearSelected();
string[] selectedCategories = selectedRecipe.SubItems[3].Text.Split(new string[] { ", " }, StringSplitOptions.None);
foreach (string selectedCategory in selectedCategories)
{
int choiceIndex = CategoryCheckedListBox.Items.IndexOf(selectedCategory);
if (choiceIndex != -1)
{
CategoryCheckedListBox.SetItemChecked(choiceIndex, true);
}
}
}
}
