请各位高手帮我看看这段C#代码实现的什么功能

ublic class Class1
{
    //SqlConnection myConnection = new SqlConnection(ConfigurationSettings.AppSettings["testConnectionString"]);
    public Class1()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }
    // public static string connstring = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + System.Web.HttpContext.Current.Server.MapPath("~/App_Data/web.mdb");    public static string connstring =System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;// ConfigurationManager.AppSettings["cn"];
    public static DataSet GDS(string sql)
    {
        //OleDbDataAdapter dap = new OleDbDataAdapter(sql, connstring);
        SqlDataAdapter dap = new SqlDataAdapter(sql, connstring);
        DataSet ds = new DataSet();
        dap.Fill(ds);
        return ds;
    }
    public static void Dsql(string sql)
    {
        //  OleDbConnection conn = new OleDbConnection();
        SqlConnection conn = new SqlConnection();
        conn.ConnectionString = connstring;
        conn.Open();
        //  OleDbCommand cmd = new OleDbCommand(sql, conn);
        SqlCommand cmd = new SqlCommand(sql, conn);
        cmd.ExecuteNonQuery();
        conn.Close();
    }
    public int hsgexucute(string sql)
    {
        //myConnection.Open();
        SqlConnection conn = new SqlConnection();
        conn.ConnectionString = connstring;
        SqlCommand myCommand = new SqlCommand(sql, conn);        SqlCommand cmd = new SqlCommand(sql, conn);
        try
        {
            conn.Open();
            myCommand.ExecuteNonQuery();
            return 1;
        }
        catch
        {
            //Console.WriteLine("SqlException:{0}",SQLexc);
            return 0;        }
        finally
        {
            conn.Close();
        }
    }    public DataSet hsggetdata(string sql)
    {
        //myConnection.Open();        //SqlConnection myConnection=new SqlConnection(ConfigurationSettings.AppSettings["strConn"]);        SqlConnection conn = new SqlConnection();
        conn.ConnectionString = connstring;
        SqlCommand myCommand = new SqlCommand(sql, conn);        SqlCommand cmd = new SqlCommand(sql, conn);        try
        {
            // myConnection.Open();            SqlDataAdapter da = new SqlDataAdapter(myCommand);
            DataSet ds = new DataSet();
            da.Fill(ds);            return ds;
        }
        catch
        {
            //Console.WriteLine("SqlException:{0}",SQLexc);
            return null;        }
        finally
        {
            conn.Close();
        }
    }