/// <summary> /// linq分页查询 /// </summary> /// <param name="expression"></param> /// <param name="func"></param> /// <param name="orderexpression"></param> /// <param name="pageIndex"></param> /// <param name="pageSize"></param> /// <param name="context"></param> /// <returns></returns> public static PageResult <T> QueryPage <T, TP, TO>(this IDBContext <T> context, Expression <Func <T, TP> > expression, Expression <Func <T, bool> > func, Expression <Func <TP, TO> > orderexpression, int pageIndex, int pageSize) where T : BaseEntity <T>, new() { var entity = new T(); var h = new ExpressionHelper(); //解析表达式 h.ResolveExpression(func); var paramters = h.Paras; var props = ExpressionHelper.GetProps(expression); var order = orderexpression == null ? "" : ExpressionHelper.GetProps(orderexpression)[0]; var sql = entity.GetQuerySQL(""); string cols = string.Join(",", props); sql = string.Format("select {0} from ( {1} ) Tab ", cols, sql); if (!h.SqlWhere.IsNullOrEmpty()) { sql += " where " + h.SqlWhere; } ISQLContext sqlContext = new SQLContext(context.Session); var total = sqlContext.GetResult <int>(string.Format("SELECT COUNT(1) FROM ({0}) a", sql), h.GetParameters()); int start = (pageIndex - 1) * pageSize; var tempsql = "select *,ROW_NUMBER() OVER(ORDER BY " + order + ") rn from ({0}) a "; sql = string.Format(tempsql, sql); sql = "SELECT TOP " + pageSize + " * FROM (" + sql + ") query WHERE rn > " + start + " ORDER BY rn"; var reader = sqlContext.ExecuteQueryReader(sql, paramters.ToArray()); var entities = DataReaderHelper.ReaderToList <T>(reader); return(new PageResult <T>(entities, total)); }
/// <summary> /// 查询分页数据-部分字段 /// </summary> /// <param name="where"></param> /// <param name="pageIndex"></param> /// <param name="pageSize"></param> /// <param name="total"></param> /// <returns></returns> public static PageResult <T> QueryPage <T, TP, TO>(this IDBContext <T> context, Expression <Func <T, TP> > expression, string where, IDictionary <string, object> paras, Expression <Func <TP, TO> > orderexpression, int pageIndex, int pageSize) where T : BaseEntity <T>, new() { if (SQLWordFilte.CheckKeyWord(@where)) { throw new Exception("您提供的关键字有可能危害数据库,已阻止执行"); } var props = ExpressionHelper.GetProps(expression); var order = orderexpression == null ? "" : ExpressionHelper.GetProps(orderexpression)[0]; var parasList = new List <SqlParameter>(); var parasListData = new List <SqlParameter>(); if (paras != null) { foreach (var para in paras) { parasList.Add(new SqlParameter(para.Key, para.Value)); parasListData.Add(new SqlParameter(para.Key, para.Value)); } } ISQLContext sqlContext = new SQLContext(context.Session); var entity = new T(); string sql = entity.GetQuerySQL(@where); var cols = string.Join(",", props); sql = string.Format("select {0} from ( {1} ) Tab ", cols, sql); var total = sqlContext.GetResult <int>(string.Format("SELECT COUNT(1) FROM ({0}) a", sql), parasList.ToArray()); int start = (pageIndex - 1) * pageSize; var tempsql = "select *,ROW_NUMBER() OVER(ORDER BY " + order + ") rn from ({0}) a "; sql = string.Format(tempsql, sql); sql = "SELECT TOP " + pageSize + " * FROM (" + sql + ") query WHERE rn > " + start + " ORDER BY rn"; var reader = sqlContext.ExecuteQueryReader(sql, parasListData.ToArray()); var entities = DataReaderHelper.ReaderToList <T>(reader); return(new PageResult <T>(entities, total)); }
/// <summary> /// linq分页查询 /// </summary> /// <param name="func"></param> /// <param name="orderby"></param> /// <param name="pageIndex"></param> /// <param name="pageSize"></param> /// <param name="total"></param> /// <returns></returns> public static PageResult <T> QueryPage <T, TO>(this IDBContext <T> context, Expression <Func <T, bool> > func, Expression <Func <T, TO> > orderexpression, int pageIndex, int pageSize) where T : BaseEntity <T>, new() { var entity = new T(); var h = new ExpressionHelper(); //解析表达式 h.ResolveExpression(func); var paramters = h.Paras; var sql = entity.GetQuerySql(""); sql = string.Format("select * from ( {0} ) Tab ", sql); if (!h.SqlWhere.IsNullOrEmpty()) { sql += " where " + h.SqlWhere; } ISQLContext sqlContext = new SQLContext(context.Session); var total = sqlContext.GetResult <int>(string.Format("SELECT COUNT(1) FROM ({0}) a", sql), h.GetParameters()); var order = orderexpression == null ? "" : ExpressionHelper.GetProps(orderexpression)[0]; int start = (pageIndex - 1) * pageSize; var tempsql = "select *,ROW_NUMBER() OVER(ORDER BY " + order + ") rn from ({0}) a "; sql = string.Format(tempsql, sql); sql = "SELECT TOP " + pageSize + " * FROM (" + sql + ") query WHERE rn > " + start + " ORDER BY rn"; var reader = (DbDataReader)sqlContext.ExecuteQueryReader(sql, paramters.ToArray()); List <T> listdata = new List <T>(); using (reader) { var tuple = reader.GetDeserializerState <T>(); while (reader.Read()) { listdata.Add((T)tuple.Func(reader)); } } return(new PageResult <T>(listdata, total)); }