/// <summary>
 /// 删除文章关键字记录
 /// </summary>
 /// <param name="keywordConnId"></param>
 /// <returns></returns>
 public static bool delKeywordConnecion(List <int> keywordConnId)
 {
     try
     {
         using (var db = new PaperDbEntities())
         {
             foreach (int id in keywordConnId)
             {
                 KeyWordConnection kc = db.KeyWordConnection.Single(a => a.id == id);
                 db.KeyWordConnection.Remove(kc);
             }
             db.SaveChanges();
         }
         return(true);
     }
     catch (Exception ex)
     {
         return(false);
     }
 }
 /// <summary>
 /// 添加关键字
 /// </summary>
 /// <param name="articleId">文章id</param>
 /// <param name="keywordId">关键字id 列表</param>
 /// <returns>是否成功</returns>
 public static bool addKeywords(int articleId, List <int> keywordId)
 {
     try
     {
         using (var db = new PaperDbEntities())
         {
             //增加所有关键字
             foreach (int id in keywordId)
             {
                 KeyWordConnection kc = new KeyWordConnection();
                 kc.ArticleId = articleId;
                 kc.KeyWordId = id;
                 db.KeyWordConnection.Add(kc);
             }
             db.SaveChanges();
             return(true);
         }
     }
     catch (Exception ex)
     {
         return(false);
     }
 }