asp.net gridview sort without data rebind

Question

I am trying to make a gridview sortable which uses a stored procedure as a datasource, I would not want it to rerun the query each time to achieve this. How would I get it to work my current code is:

protected override void OnPreRender(EventArgs e)
{
    if (!IsPostBack)
    {
    SqlCommand cmd2 = new SqlCommand("SR_Student_Course_List", new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["RDCV2ConnectionString"].ConnectionString));
    try
    {
        cmd2.CommandType = CommandType.StoredProcedure;
        cmd2.CommandTimeout = 120;
        cmd2.Parameters.Add("student_id", SqlDbType.Char, 11).Value = student;
        cmd2.Connection.Open();
        grdCourses.DataSource = cmd2.ExecuteReader();
        grdCourses.DataSourceID = string.Empty;
        grdCourses.DataBind();
    } finally
    {
        cmd2.Connection.Close();
        cmd2.Connection.Dispose();
        cmd2.Dispose();
    }}}

This code just binds the data when it isn't a postback, the gridview has viewstate enabled. On pressing the column headers a postback happens but no sorting occurs. If anyone has a simple fix for this please let me know or even better an ajax sort which would avoid the postback would be even better. The dataset is relatively small however takes a long time to query which is why I would not like to requery on each sort.

Answer 1

You could try storing the data in view state (or cache).

Answer 2

If you are not paging the results, and just doing a read, then something like the jquery tablesorter plugin would be a quick and easy fix. I have used this on tables of up to 1400 rows and works great, although ~> few hundred probably better on slow putas.

If the gridview is editable, then aspnet event/input validation might spit a dummy if you don't go through the proper registration of client scripts etc.

Answer 3

In your case, I would use a SqlDataAdapter and fill a DataTable. Then, put the DataTable into a Session variable. When the GridView is sorting, check if the Session variable still exists. If it does not, then fill the DataTable again. Finally sort the DataTable using a DataView and rebind the GridView with the DataView.