/// <summary>
/// 获取所有的新闻分类
/// </summary>
/// <returns></returns>
public List <NewsCategory> GetAllCategory()
{
using (HotelDBEntities db = new DAL.HotelDBEntities())
{
return((from c in db.NewsCategory select c).ToList());
}
}
/// <summary>
/// 根据新闻Id查询新闻详细
/// </summary>
/// <param name="newsId"></param>
/// <returns></returns>
public News GetNewsById(int newsId)
{
using (HotelDBEntities db = new DAL.HotelDBEntities())
{
return((from n in db.News where n.NewsId == newsId select n).FirstOrDefault());
}
}
/// <summary>
/// 根据新闻分类ID查询分类名称
/// </summary>
/// <param name="categoryId"></param>
/// <returns></returns>
public string GetCategoryName(int categoryId)
{
using (HotelDBEntities db = new DAL.HotelDBEntities())
{
return((from c in db.NewsCategory
where c.CategoryId == categoryId
select c.CategoryName).FirstOrDefault());
}
}
/// <summary>
/// 发布新闻：添加
/// </summary>
/// <param name="news"></param>
/// <returns></returns>
//public int PublishNews(News news)
//{
// //using (HotelDBEntities db = new HotelDBEntities())
// //{
// // db.News.Add(news);
// // return db.SaveChanges();
// //}
// return helper.Add<News>(news);
//}
//【下面是使用存储过程】
public int PublishNews(News news)
{
SqlParameter[] param = new SqlParameter[]
{
new SqlParameter("@NewsTitle", news.NewsTitle),
new SqlParameter("@NewsContents", news.NewsContents),
new SqlParameter("@CategoryId", news.CategoryId)
};
using (HotelDBEntities db = new DAL.HotelDBEntities())
{
return(db.Database.ExecuteSqlCommand("execute usp_AddNews @NewsTitle,@NewsContents,@CategoryId", param));
}
}
/// <summary>
/// 查询指定前几条新闻
/// </summary>
/// <param name="count"></param>
/// <returns></returns>
public List <News> GetNews(int count)
{
using (HotelDBEntities db = new DAL.HotelDBEntities())
{
//下面这条语句没有管理对象的查询
//return (from n in db.News
// orderby n.PublishTime descending
// select n).Take(count).ToList();
//通过下面发方法查询关联对象
var newsList = (from n in db.News
orderby n.PublishTime descending
select new
{
n.NewsId,
n.NewsTitle,
n.PublishTime,
n.NewsContents,
n.CategoryId,
n.NewsCategory.CategoryName
}).Take(count);
//转换成具体对象
List <News> list = new List <News>();
foreach (var item in newsList)
{
list.Add(new News
{
NewsId = item.NewsId,
NewsTitle = item.NewsTitle,
NewsContents = item.NewsContents,
PublishTime = item.PublishTime,
CategoryId = item.CategoryId,
NewsCategory = new NewsCategory {
CategoryName = item.CategoryName
}
});
}
return(list);
}
}
