ADO.NET 对数据操作

public static class SQLHelper ???{ ???????static string connString = ConfigurationManager.ConnectionStrings["connString"].ToString(); ???????/// <summary> ???????/// 执行增删改 ???????/// </summary> ???????/// <param name="sql"></param> ???????/// <returns></returns> ???????public static int Update(string sql) ???????{ ???????????SqlConnection conn = new SqlConnection(connString); ???????????SqlCommand cmd = new SqlCommand(sql, conn); ???????????try ???????????{ ???????????????conn.Open(); ???????????????return cmd.ExecuteNonQuery(); ???????????} ???????????catch (Exception ex) ???????????{ ???????????????throw new Exception(ex.Message); ???????????} ???????????finally ???????????{ ???????????????conn.Close(); ???????????} ???????} ???????/// <summary> ???????/// 执行单一结果查询 ???????/// </summary> ???????/// <param name="sql"></param> ???????/// <returns></returns> ???????public static object GetSingleResult(string sql) ???????{ ???????????SqlConnection conn = new SqlConnection(connString); ???????????SqlCommand cmd = new SqlCommand(sql, conn); ???????????try ???????????{ ???????????????conn.Open(); ???????????????return cmd.ExecuteScalar(); ???????????} ???????????catch (Exception ex) ???????????{ ???????????????throw new Exception(ex.Message); ???????????} ???????????finally ???????????{ ???????????????conn.Close(); ???????????} ???????} ???????/// <summary> ???????/// 执行一个结果集查询 ???????/// </summary> ???????/// <param name="sql"></param> ???????/// <returns></returns> ???????public static SqlDataReader GetReader(string sql) ???????{ ???????????SqlConnection conn = new SqlConnection(connString); ???????????SqlCommand cmd = new SqlCommand(sql, conn); ???????????try ???????????{ ???????????????conn.Open(); ???????????????return cmd.ExecuteReader(CommandBehavior.CloseConnection); ???????????} ???????????catch (Exception ex) ???????????{ ???????????????conn.Close(); ???????????????throw new Exception(ex.Message); ???????????} ???????????finally ???????????{ ???????????????conn.Close(); ???????????} ???????} ???????/// <summary> ???????/// 执行返回数据集的查询 ???????/// </summary> ???????/// <param name="sql"></param> ???????/// <returns></returns> ???????public static SqlDataAdapter GetDataSet(string sql) ???????{ ???????????SqlConnection conn = new SqlConnection(connString); ???????????SqlCommand cmd = new SqlCommand(sql, conn); ???????????//创建适配器对象 ???????????SqlDataAdapter da = new SqlDataAdapter(cmd); ???????????DataSet ds = new DataSet(); ???????????try ???????????{ ???????????????conn.Open(); ???????????????da.Fill(ds);//使用数据适配器填充数据集 ???????????????return da; ???????????} ???????????catch (Exception ex) ???????????{ ???????????????throw new Exception(ex.Message); ???????????} ???????????finally ???????????{ ???????????????conn.Close(); ???????????} ???????} ???}