public static class QueryAssembly

     {

         /// <summary>

         /// 返回true

         /// </summary>

         /// <typeparam name="T"></typeparam>

         /// <returns></returns>

         public static Expression<Func<T, bool>> True<T>()

         {

             return f => true;

         }

         /// <summary>

         /// false

         /// </summary>

         /// <typeparam name="T"></typeparam>

         /// <returns></returns>

         public static Expression<Func<T, bool>> False<T>()

         {

             return f => false;

         }

         /// <summary>

         /// or

         /// </summary>

         /// <typeparam name="T"></typeparam>

         /// <param name="expr1"></param>

         /// <param name="expr2"></param>

         /// <returns></returns>

         public static Expression<Func<T, bool>> Or<T>(this Expression<Func<T, bool>> expr1,Expression<Func<T, bool>> expr2)

         {

             var invokedExpr = Expression.Invoke(expr2, expr1.Parameters.Cast<Expression>());

             return Expression.Lambda<Func<T, bool>>

                   (Expression.Or(expr1.Body, invokedExpr), expr1.Parameters);

         }

         /// <summary>

         /// and

         /// </summary>

         /// <typeparam name="T"></typeparam>

         /// <param name="expr1"></param>

         /// <param name="expr2"></param>

         /// <returns></returns>

         public static Expression<Func<T, bool>> And<T>(this Expression<Func<T, bool>> expr1,Expression<Func<T, bool>> expr2)

         {

             var invokedExpr = Expression.Invoke(expr2, expr1.Parameters.Cast<Expression>());

             return Expression.Lambda<Func<T, bool>>

                   (Expression.And(expr1.Body, invokedExpr), expr1.Parameters);

         }

     }

 public class Paging<T>

     {

         /// <summary>

         /// 当前页码

         /// </summary>

         [DataMember]

         public int PageNo { get; set; }

         /// <summary>

         /// 总页数

         /// </summary>

         [DataMember]

         public int PageCount { get; set; }

         /// <summary>

         /// 每页记录数

         /// </summary>

         [DataMember]

         public int PageSize { get; set; }

         /// <summary>

         /// 总记录数

         /// </summary>

         [DataMember]

         public int RecordCount { get; set; }

         /// <summary>

         /// 当前页的数据

         /// </summary>

         [DataMember]

         public List<T> CurrentList { get; set; }

     }

 public Paging<DAML> QueryAJML(int pageNo, int pageSize,DAML data)

         {

             Paging<DAML> result = null;

             Expression<Func<DAML, bool>> ExpWhere = QueryAssembly.True<DAML>();

             using (IStatelessSession session = _sessionFactory.OpenStatelessSession())

             {

                 var queryDAML = session.Query<DAML>();

                 if (!string.IsNullOrEmpty(data.MLH))

                 {

                     ExpWhere=ExpWhere.Or(x=>x.MLH.Contains(data.MLH));

                 }

                 if (!string.IsNullOrEmpty(data.QZH))

                 {

                     ExpWhere = ExpWhere.Or(x => x.MLH.Contains(data.QZH));

                 }

                 //查询

                 queryDAML.Where(ExpWhere);

                 //排序

                 queryDAML.OrderBy(x=>x.ID);

                 //页数

                 result.PageNo = pageNo;

                 //每页记录数

                 result.PageSize = pageSize;

                 //总记录数

                 result.RecordCount = queryDAML.Count();

                 //总页数

                 result.PageCount = (result.RecordCount + result.PageSize - ) / result.PageSize;

                 //返回数据

                 result.CurrentList = new List<DAML>();

                 result.CurrentList = queryDAML.ToList();

             }

             return result;

         }