旧版数据库操作类

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

/// <summary>
/// Class1 的摘要说明
/// </summary>
public class OperDB
{
    bool autoCloseConn;
    SqlConnection conn=new SqlConnection();
    public OperDB(bool autoCloseConn)
    {
        this.autoCloseConn = autoCloseConn;
        conn.ConnectionString = ConfigurationManager.AppSettings["connjy"].ToString();
        conn.Open();
    }
    public OperDB(bool autoCloseConn,string connname)
    {
        this.autoCloseConn = autoCloseConn;
        if (connname.Equals("connjy"))
        {
            conn.ConnectionString = ConfigurationManager.AppSettings["connjy"].ToString();
        }
        else if(connname.Equals("connjf"))
        {
            conn.ConnectionString = ConfigurationManager.AppSettings["connjf"].ToString();
        }
        conn.Open();
    }
    public int InsertOrUpdate(string sql)
    {
        SqlCommand cmd = new SqlCommand(sql, conn);
        return cmd.ExecuteNonQuery();
    }
    public SqlDataReader Select(string sql)
    {
        SqlCommand cmd = new SqlCommand(sql, conn);
        SqlDataReader reader= cmd.ExecuteReader();        
        return reader;
    }
    public string selectvalue(string sql)
    {
        string a="";
        SqlCommand cmd = new SqlCommand(sql, conn);
        SqlDataReader reader = cmd.ExecuteReader();
        if (reader.Read())
        {
            a = reader[0].ToString().Trim();
        }
        reader.Close();
        return a;
    }
    //是否自动关闭数据库。如果程序员要求自动关闭数据库连接，    
    private void CloseConn()
    {
        if(autoCloseConn)
        {
        try
        { conn.Close(); }
        catch
        { }
        }
    }
    //当构造此函数时，不要求要求关闭数据库。那么要显示调用该函数
    public void Close()
    {
        try
        { conn.Close(); }
        catch
        { }
    }
}