How to paging gridView

[bedomedo]

I have grid view with this :\[code\] <asp:GridView ID="GridViewCosts" runat="server" CellPadding="4" ForeColor="#333333" GridLines="None" ShowFooter="True" ShowHeaderWhenEmpty="True" AutoGenerateColumns="False" OnRowDeleting="GridViewCosts_RowDeleting" Width="387px" OnSelectedIndexChanged="GridViewCosts_SelectedIndexChanged" AllowPaging="true" AllowSorting="true" PageSize="5" >\[/code\]but this give in me error: \[code\]The data source does not support server-side data paging.\[/code\]in code behind i have something like this : \[code\]GridViewCosts.DataSource = rdr;Line 55: GridViewCosts.DataBind();\[/code\]how to paging my gridView which isn't have dataSource UPDATEI modify I have this \[code\] <asp:GridView ID="GridViewCosts" runat="server" CellPadding="4" ForeColor="#333333" GridLines="None" ShowFooter="True" ShowHeaderWhenEmpty="True" AutoGenerateColumns="False" OnRowDeleting="GridViewCosts_RowDeleting" Width="387px" OnSelectedIndexChanged="GridViewCosts_SelectedIndexChanged" OnPageIndexChanging="GridViewCosts_PageIndexChanging" PageSize="5" >\[/code\]in code Behind have this : \[code\] public void getViewProfit() { string connectionString = cs.getConnection(); string query = "select Id ,name,value,Description,DateCreate from AllCostView where IdUser = '" + cui.getCurrentId() + "'"; using (SqlConnection myConnection = new SqlConnection(connectionString)) { myConnection.Open(); SqlCommand command = new SqlCommand(query, myConnection); using (SqlDataReader rdr = command.ExecuteReader()) { GridViewCosts.DataSource = rdr; GridViewCosts.DataBind(); } } } protected void GridViewCosts_PageIndexChanging(object sender, GridViewPageEventArgs e) { GridViewCosts.PageIndex = e.NewPageIndex; getViewProfit(); }\[/code\]there no error any more , but still not show paging