不成功的MVC Repository模式,记录下来,后面看看原因在哪里(二) Repository类

  1  public class Repository<T> : IRepository<T> where T : class
  2     {
  3         public WBIDbContext m_Context=WBIContextFactory.GetCurrentContext();//上下文数据库
  4         public DbSet<T> dbSet;
  5         public Repository(WBIDbContext dbContext)
  6         {
  7             this.m_Context = dbContext;
  8             this.dbSet = dbContext.Set<T>();
  9         }
 10 
 11         protected IRepository<T> m_currentRepository1 { get; set; }
 12         protected IDevTypeRepository m_currentRepository { get; set; }
 13         public Repository(IDevTypeRepository currentRepository)
 14         {
 15             m_currentRepository = currentRepository;
 16         }
 17 
 18         public T Add(T entity)
 19         {
 20             //设置实体的状态 add
 21             m_Context.Entry<T>(entity).State = System.Data.Entity.EntityState.Added;
 22             //将上下文中所做的更改保存到数据库中
 23             m_Context.SaveChanges();
 24             //返回保存后的实体
 25             return entity;
 26         }
 27 
 28         public bool Update(T entity)
 29         {
 30             m_Context.Set<T>().Attach(entity);
 31             m_Context.Entry<T>(entity).State = System.Data.Entity.EntityState.Modified;
 32             return m_Context.SaveChanges() > 0;
 33         }
 34 
 35         public bool Delete(T entity)
 36         
 37         {
 38             m_Context.Set<T>().Attach(entity);
 39             m_Context.Entry<T>(entity).State = System.Data.Entity.EntityState.Deleted;
 40             return m_Context.SaveChanges() > 0;
 41         }
 42 
 43         //名字是否为空
 44         public bool CheckNameIsEmpty(Expression<Func<T, bool>> whereLambda)
 45         {
 46             return m_Context.Set<T>().Any(whereLambda);
 47         }
 48 
 49         //名字是否存在
 50         public bool CheckNameExist(Expression<Func<T, bool>> whereLambda)
 51         {
 52             return m_Context.Set<T>().Any(whereLambda);
 53         }
 54         //检查其他项
 55         public bool Check(Expression<Func<T, bool>> whereLambda)
 56         {
 57             return m_Context.Set<T>().Any(whereLambda);
 58         }
 59         //保存
 60         //public void Save()
 61         //{
 62         //    m_Context.SaveChanges();
 63  
 64         //}
 65 
 66         public int Count(Expression<Func<T, bool>> predicate)
 67         {
 68             return m_Context.Set<T>().Count(predicate);
 69         }
 70 
 71         public List<T> ToList()
 72         {
 73             return m_Context.Set<T>().ToList();
 74         }
 75 
 76         public T Find(Expression<Func<T, bool>> whereLambda)
 77         {
 78             T entity = m_Context.Set<T>().FirstOrDefault<T>(whereLambda);
 79             return entity;
 80         }
 81 
 82         public IQueryable<T> FindList(Expression<Func<T, bool>> whereLamba, string orderName, bool isAsc)
 83         {
 84             var list = m_Context.Set<T>().Where(whereLamba);
 85             list = OrderBy(list, orderName, isAsc);
 86             return list;
 87         }
 88 
 89         public IQueryable<T> FindList<S>(Expression<Func<T, bool>> whereLambda, bool isAsc, Expression<Func<T, S>> orderLamba)
 90         {
 91             var list = m_Context.Set<T>().Where<T>(whereLambda);
 92             if (isAsc)
 93             {
 94                 list = list.OrderBy<T, S>(orderLamba);
 95             }
 96             else
 97             {
 98                 list = list.OrderByDescending<T, S>(orderLamba);//降序排列
 99             }
100             return list;
101         }
102 
103 
104 
105 
106         public IQueryable<T> FindPageList<S>(int pageIndex, int pageSize, out int totalRecordCnt,
107     Expression<Func<T, bool>> whereLamdba, bool isAsc, Expression<Func<T, S>> orderLambda)
108         {
109             var list = m_Context.Set<T>().Where<T>(whereLamdba);
110             totalRecordCnt = list.Count();
111 
112             if (isAsc)
113             {
114                 list = list.OrderBy<T, S>(orderLambda)
115                     .Skip<T>((pageIndex - 1) * pageSize).Take<T>(pageSize);
116             }
117             else
118             {
119                 list = list.OrderByDescending<T, S>(orderLambda)
120                     .Skip<T>((pageIndex - 1) * pageSize).Take<T>(pageSize);
121             }
122 
123             return list;
124         }
125 
126 
127 
128         #region Private Methods
129         /// <summary>
130         /// 排序
131         /// </summary>
132         /// <typeparam name="T">类型</typeparam>
133         /// <param name="source">原IQueryable</param>
134         /// <param name="propertyName">排序属性名</param>
135         /// <param name="isAsc">是否升序</param>
136         /// <returns>排序后的IQueryable</returns>
137         private IQueryable<T> OrderBy(IQueryable<T> source, string propertyName, bool isAsc)
138         {
139             if (source == null)
140             {
141                 throw new ArgumentNullException("source", "不能为空");
142             }
143             if (string.IsNullOrEmpty(propertyName))
144             {
145                 return source;
146             }
147             var parameter = Expression.Parameter(source.ElementType);
148             var property = Expression.Property(parameter, propertyName);
149             if (property == null)
150             {
151                 throw new ArgumentNullException("propertyName", "属性不存在");
152             }
153             var lambda = Expression.Lambda(property, parameter);
154             var methodName = isAsc ? "OrderBy" : "OrderByDescending";
155             var resultExpression = Expression.Call(typeof(Queryable), methodName,
156                 new Type[] { source.ElementType, property.Type }, source.Expression, Expression.Quote(lambda));
157             return source.Provider.CreateQuery<T>(resultExpression);
158         }
159         #endregion
160     }

 

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