分页读取数据

/// <summary> /// 分页读取数据 /// </summary> /// <param name="query">select查询语句</param> /// <param name="pageSize">每页显示数据数</param> /// <param name="currentPageIndex">当前页码</param> /// <param name="dt">存储数据的DataTable实例</param> public static void FillDataTable(string query,int pageSize,int currentPageIndex, DataTable dt) { //读取数据的开始索引 long startIndex = (currentPageIndex - 1) * pageSize; //读取数据的结束索引 long endIndex = currentPageIndex * pageSize-1; //DataReader读取的当前数据行的索引 long readToIndex = -1; using (SqlConnection conn = new SqlConnection(ConnString)) { SqlCommand cmd = new SqlCommand(query, conn); conn.Open(); SqlDataReader dr = cmd.ExecuteReader(); //数据源中的列数 int cols = dr.VisibleFieldCount; //构造DataTable结构 for (int i = 0; i < cols; i++) { dt.Columns.Add(new DataColumn(dr.GetName(i), dr.GetFieldType(i))); } //读取数据，将数据一行一行添加到DataTable while (dr.Read()) { readToIndex++; //当DataReader指针在开始索引和结束索引闭区间时才读取数据构造DataRow //并添加到DataTable if (readToIndex >= startIndex && readToIndex <= endIndex) { DataRow row = dt.NewRow(); for (int i = 0; i < cols; i++) { row[i] = dr[i]; } dt.Rows.Add(row); } } dr.Close(); } } }}