List data in gridview using objects and class or in procedural method?

Try this in Class
Public DataSet GetData()
{
   SqlConnection _sqlcncn=new SqlConnection("ConnectionString);
 SqlCommand  sqlcmd = new SqlCommand("Select Query", sqlcn);
          
          
           // sqlcmd.CommandType = CommandType.StoredProcedure;
            sqlcn.Open();
            DataSet ds = new DataSet();
            sqlda = new SqlDataAdapter(sqlcmd);
            sqlda.Fill(ds);
            return ds;
}

In code behind call this method like bello
DataSet ds=Class.GetData();
Gridview.DataSource=ds.Tables[0];
GridView.DataBind();