public ActionResult Create()
{
var posts = new Posts();
posts.category = new List<Category>();
PopulateCategories(posts);
return View();
}
private void PopulateCategories(Posts post)
{
var allCategories = db.Category;
var assignedCategories = new HashSet<int>(post.category.Select(i => i.id));
var viewModel = new List<linkedCategories>();
foreach (var category in allCategories)
{
viewModel.Add(new linkedCategories
{
id = category.id,
title = category.title,
linked = assignedCategories.Contains(category.id)
});
}
ViewBag.Categories = viewModel;
}
public void updateCategories(string[] selectedCategories, Posts postToUpdate)
{
if (selectedCategories == null)
{
postToUpdate.category = new List<Category>();
return;
}
var hsSelectedCategories = new HashSet<string>(selectedCategories);
var postCategory = new HashSet<int>
(postToUpdate.category.Select(i => i.id));
foreach ( var category in db.Category)
{
if (hsSelectedCategories.Contains(category.id.ToString()))
{
if (!postCategory.Contains(category.id))
{
postToUpdate.category.Add(category);
}
}
else
{
if (postCategory.Contains(category.id))
{
postToUpdate.category.Remove(category);
}
}
}
}