sqlHelper

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Data.SqlClient;

/// <summary>
///MySqlHelper 的摘要说明
/// </summary>
public class MySqlHelper
{
    protected static SqlConnection conn = new SqlConnection();
    protected static SqlCommand comm = new SqlCommand();

    public MySqlHelper()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }
    /// <summary>
    /// 打开数据库连接


    /// </summary>
    private static void OpenConnection()
    {
        if (conn.State == ConnectionState.Closed)
        {
            conn.ConnectionString = "server=.;database=pubs;user=sa;pwd=database";
            comm.Connection = conn;
            try
            {
                conn.Open();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }
    }
    /// <summary>
    /// 关闭数据库连接


    /// </summary>
    private static void CloseConnection()
    {
        if (conn.State == ConnectionState.Open)
        {
            conn.Close();
            conn.Dispose();
            comm.Dispose();
        }
    }
    /// <summary>
    /// 执行数据库语句


    /// </summary>
    /// <param name="sqlStr">数据库语句</param>
    public static void ExcuteSql(string sqlStr)
    {
        try
        {
            OpenConnection();
            comm.CommandType = CommandType.Text;
            comm.CommandText = sqlStr;
            comm.ExecuteNonQuery();
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
        finally
        {
            CloseConnection();
        }
    }
    /// <summary>
    /// 返回指定sql语句的OleDbDataReader对象，使用时请注意关闭这个对象


    /// </summary>
    /// <param name="sqlStr">数据库语句</param>
    /// <returns>SqlDataReader</returns>
    public static SqlDataReader DataReader(string sqlStr)
    {
        SqlDataReader dr = null;
        try
        {
            OpenConnection();
            comm.CommandType = CommandType.Text;
            comm.CommandText = sqlStr;
            dr = comm.ExecuteReader(CommandBehavior.CloseConnection);
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
        finally
        {
            dr.Close();
            CloseConnection();
        }
        return dr;
    }
    /// <summary>
    /// 返回指定sql语句的dataset
    /// </summary>
    /// <param name="sqlStr">数据库语句</param>
    /// <returns>DataSet</returns>
    public static DataSet DataSet(string sqlStr)
    {
        DataSet ds = new DataSet();
        SqlDataAdapter da = new SqlDataAdapter();
        try
        {
            OpenConnection();
            comm.CommandType = CommandType.Text;
            comm.CommandText = sqlStr;
            da.SelectCommand = comm;
            da.Fill(ds);
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
        finally
        {
            CloseConnection();
        }
        return ds;
    }
    /// <summary>
    /// 返回指定sql语句的datatable
    /// </summary>
    /// <param name="sqlStr"></param>
    /// <returns></returns>
    public static DataTable DataTable(string sqlStr)
    {
        DataTable dt = new DataTable();
        SqlDataAdapter da = new SqlDataAdapter();
        try
        {
            OpenConnection();
            comm.CommandType = CommandType.Text;
            comm.CommandText = sqlStr;
            da.SelectCommand = comm;
            da.Fill(dt);
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
        finally
        {
            CloseConnection();
        }
        return dt;
    }
}