public override async Task <IViewProviderResult> BuildUpdateAsync(CategoryAdmin category,
IViewProviderContext context)
{
// Get posted role names
var rolesToAdd = GetRolesToAdd();
// Update model
var model = new EditUserRolesViewModel
{
SelectedRoles = rolesToAdd
};
if (!await context.Updater.TryUpdateModelAsync(model))
{
return(await BuildEditAsync(category, context));
}
if (context.Updater.ModelState.IsValid)
{
// Remove roles in two steps to prevent an iteration on a modified collection
var rolesToRemove = new List <string>();
foreach (var role in await _categoryManager.GetRolesAsync(category))
{
if (!rolesToAdd.Contains(role))
{
rolesToRemove.Add(role);
}
}
foreach (var role in rolesToRemove)
{
await _categoryManager.RemoveFromRoleAsync(category, role);
}
// Add new roles
foreach (var role in rolesToAdd)
{
if (!await _categoryManager.IsInRoleAsync(category, role))
{
await _categoryManager.AddToRoleAsync(category, role);
}
}
}
return(await BuildEditAsync(category, context));
}
