Question

The .aspx:

 <asp:GridView ID="gvFirst" runat="server" AutoGenerateColumns="false" 
        AllowPaging="true" 
        ondatabound="gvFirst_DataBound" >
        <Columns>
            <asp:BoundField DataField="ID" HeaderText="ProductID"/>
            <asp:BoundField DataField="Name" HeaderText="ProductName" />
        </Columns>
        <PagerTemplate>
            <asp:Panel ID="pnlPager" runat="server">
            </asp:Panel>
        </PagerTemplate>
    </asp:GridView>

The .cs:

 public class Productinformation
    {
     public int PID
     {
         get;
         set;
     }
     public string PName
     {
         get;
         set;
     }
    }
       using (NorthWindDataContext _NorthWindDataContext = new NorthWindDataContext())
        {
            Proinfo = new List<Productinformation>();
            Proinfo = (from p in _NorthWindDataContext.Products
                       select new Productinformation
                       {
                           PID = p.ProductID,
                           PName = p.ProductName,
                       }).ToList();

            gvFirst.DataSource =  Proinfo.Take(PageSize) ;
            gvFirst.DataBind();
        }

Proinfo variable is declared globally. Now When i run this code, it shows me the following error :

the data source does not support server-side data paging

If i use var type of variable then it is worked but
we can’t declare var type of variable globally,so if i used it, then i have to call this method every time in paging. and i don’t want to use Objectdatasource.

Answer 1

You must return a List to the gvFirst using ToList() method. So try this:

gvFirst.DataSource =  Proinfo.Take(PageSize).ToList();

Explanation:

Because on the gvFirst you set the property AllowPaging="true" than the paging can be used with any data source object that implements ICollection interface.

ProInfo.Take(PageSize) returns an IEnumerable and this is why you need to call the ToList() method.