private async Task SaveCategory(List <Guid> newCategoryIDs, Bookmark bookmark)
{
//删除旧的未选择的分类
foreach (var oldCategory in bookmark.Categorys)
{
var category = await _categoryRepository.GetAsync(oldCategory.CategoryId);
//旧的分类在新分类中是否存在
var oldCategoryNameInNewCategorys = newCategoryIDs.FirstOrDefault(t => t == category.Id);
if (oldCategoryNameInNewCategorys == null)
{
bookmark.RemoveCategory(oldCategory.CategoryId);
category.DecreaseUsageCount();
await _categoryRepository.UpdateAsync(category);
}
else
{
newCategoryIDs.Remove(oldCategoryNameInNewCategorys);
}
}
//添加新选中的分类
foreach (var newCategoryID in newCategoryIDs)
{
var category = await _categoryRepository.GetAsync(newCategoryID);
bookmark.AddCategory(newCategoryID);
category.IncreaseUsageCount();
await _categoryRepository.UpdateAsync(category);
}
}
