Gridview sorting,paging

//Take one Grid View and Bind all the column through
//hdnSort is a Hidden field take one hidden field also.
asp:TemplateField
ItemTemplate and give the sort expression also and paging and sorting also true the property of GridView...

//Web.config file
add name="Master1" connectionString ="Data Source=.;user id=; password=; database=Master; "/>

//in aspx.cs
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["Master1"].ConnectionString);
private void bindData(string sorting)
{
DataSet ds;
SqlDataAdapter da;
string sql = null;
ds = new DataSet();
da = new SqlDataAdapter();
try
{
con.Open();
}
catch (Exception ex)
{

}


sql = "Select student_id,last_name,first_name,Score from Student order by " + sorting;
da.SelectCommand = new SqlCommand(sql, con);
da.Fill(ds);

if (ds.Tables[0].Rows.Count > 0)
{
GridView1.DataSource = ds;
GridView1.DataBind();

if (ds.Tables.Count == 0)
{

//lblMessage.Text = "No record found";
}
}
ds = null;
da = null;
try { con.Close(); }
catch (Exception ex) { }

}

//call Bind Method where you bind the Gridview perform all operation

protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
bindData("student_id");

}
}

//for sorting

private string ConvertSortDirectiontoSql(SortDirection sort)
{
string newSortDirection = string.Empty;
switch (sort)
{
case SortDirection.Ascending:
newSortDirection = "Asc";
hdnSort.Value = "Asc";
break;
case SortDirection.Descending:
newSortDirection = "Desc";
hdnSort.Value = "Desc";
break;
}
return newSortDirection;

}



protected void GridView1_Sorting(object sender, GridViewSortEventArgs e)
{
//hdnSort is a Hidden field take one hidden field also.
if (hdnSort.Value.Length == 0 || hdnSort.Value == "Desc")
e.SortDirection = SortDirection.Ascending;
else
e.SortDirection = SortDirection.Descending;

string sorting = e.SortExpression + " " + ConvertSortDirectiontoSql(e.SortDirection);
if (hdnSort.Value.Length == 0)
hdnSort.Value = "Desc";
bindData(sorting);
}

//for paging

protected void GridView1_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GridView1.PageIndex = e.NewPageIndex;
bindData("student_id desc");
}