Saturday, March 24, 2012

Paging freeze after partial postback

HiI am a newbie to the AJAX stage, I created an application very similar in functionality as the to do list HDI video demo.My problem is when I do a partial page back and the new data is refreshed into my gridview the paging stops to function. You can click on the page numbers and there it will stay till I fire

a full page postback. I have an updatePanel with a Gridview and a dropdownlist included in the panel. The dropdownlist just selects different departments in our organization.

I set the updatePanel to conditionalupdate and specified my trigger as dorpdownlist selected index change, enabled the paging and enablepagingandsorting on my gridview.

What did I miss on my path to AJAX ?

Can you post your code where its freezing. Check with breakpoints?


if the dropdown is inside the panel, then you simply don't need to set up triggers.

btw, here's a quick example:

i have the following ona code file on app_code:

public class Obj
private Int32 _id;
private String _name;

public int Id
get { return _id; }
set { _id = value; }

public string Name
get { return _name; }
set { _name = value; }

public class ObjDS
public List<Obj> Get()
List<Obj> objs = new List<Obj>
new Obj{Id = 1, Name = "Luis"} ,
new Obj{Id = 2, Name = "Jose"} ,
new Obj{Id = 3, Name = "Jose"} ,
new Obj{Id = 4, Name = "Jose"}

return objs;

and then, on an aspx page, i have this:

<asp:ScriptManager runat="server" ID="manager" />
<asp:UpdatePanel runat="server" ID="panel">
<asp:GridView ID="GridView1" runat="server"
DataSourceID="source" AllowPaging="true">

ID="source" runat="server">
<%= DateTime.Now.ToString() %>

it's working here. does it work there?

Hi LuisThanks for the reply.I am using a database queried created dataset and not a custom dataset,does this make a difference?What gets me is that after the page has loaded for a first time the paging works and after a partial postback the rest of the controls workexcept the datagrid's paging.

I'll have a crack at your code and let you know.

Hi Dexza,

Here is a working sample which is written based on your description. Please compare it with yours.

<%@. Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" ""
<script runat="server"
protected void Page_Load(object sender, EventArgs e)
if (!IsPostBack)

protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)

<html xmlns="">
<head runat="server">
<title>Untitled Page</title>
<form id="form1" runat="server">
<asp:ScriptManager ID="ScriptManager1" runat="server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource1" PageSize="2" AllowPaging="true">
<asp:CommandField ShowEditButton="True" />
<asp:BoundField DataField="EmployeeID" HeaderText="EmployeeID" InsertVisible="False"
ReadOnly="True" SortExpression="EmployeeID" />
<asp:BoundField DataField="LastName" HeaderText="LastName" SortExpression="LastName" />
<asp:BoundField DataField="FirstName" HeaderText="FirstName" SortExpression="FirstName" />
<asp:BoundField DataField="Title" HeaderText="Title" SortExpression="Title" />
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NORTHWNDConnectionString%>"
SelectCommand="SELECT [EmployeeID], [LastName], [FirstName], [Title] FROM [Employees]"
DeleteCommand="DELETE FROM [Employees] WHERE [EmployeeID] = @.EmployeeID" InsertCommand="INSERT INTO [Employees] ([LastName], [FirstName], [Title]) VALUES (@.LastName, @.FirstName, @.Title)"
UpdateCommand="UPDATE [Employees] SET [LastName] = @.LastName, [FirstName] = @.FirstName, [Title] = @.Title WHERE [EmployeeID] = @.EmployeeID">
<asp:Parameter Name="EmployeeID" Type="Int32" />
<asp:Parameter Name="LastName" Type="String" />
<asp:Parameter Name="FirstName" Type="String" />
<asp:Parameter Name="Title" Type="String" />
<asp:Parameter Name="EmployeeID" Type="Int32" />
<asp:Parameter Name="LastName" Type="String" />
<asp:Parameter Name="FirstName" Type="String" />
<asp:Parameter Name="Title" Type="String" />
<asp:DropDownList ID="DropDownList1" runat="server" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged" AutoPostBack="true">
<asp:AsyncPostBackTrigger ControlID="DropDownList1" EventName="SelectedIndexChanged" />

Best regards,



Jonathan, i haven't run the code, but i'm curious: why did you associate a trigger with a server control that is inside an updatepanel?

Hi Luis Abreu,

Thanks for your attention. I just generated a sample based on the description of the thread owner. Yes , I agree with you that we don't need a trigger in this situation. Thanks

Best regards,


hello again.

well, i just asked because i might be missing something...thanks for the clarification.

Hi guys I have found my problem regarding the paging issue fromContributor post I noticed that on his properties he had only AllowPaging set to true and I had AllowPaging and EnablePagingAndSortingCallback set to true. So I changed it to false and of we go. Paging and sorting is up and running. Now I still have the problem where after selecting something different from my dorpdownlist that the updating does not work, but if I go back to the data the page was loaded with it works fine. So I have two questions. Why does the paging and sorting stop to function with a partial postback if EnablePagingAndSortingCallback is set to true. And what is wrong with the update function. Here is my code.

<%@.PageLanguage="C#"AutoEventWireup="true"CodeFile="Default.aspx.cs"Inherits="_Default"%> <%@.RegisterAssembly="AjaxControlToolkit"Namespace="AjaxControlToolkit"TagPrefix="cc1"%> <!DOCTYPEhtmlPUBLIC"-//W3C//DTD XHTML 1.1//EN"""><htmlxmlns=""><headrunat="server"> <title>Untitled Page</title> <linkhref="StyleSheet.css"rel="stylesheet"type="text/css"/></head> <body> <formid="form1"runat="server"> <asp:ScriptManagerID="ScriptManager1"runat="server"/> <br/> <br/> <br/> <br/> <asp:PanelID="Panel2"runat="server"BorderColor="Silver"BorderStyle="Solid"BorderWidth="1px" Height="50px"Width="125px"> <asp:UpdatePanelID="UpdatePanel1"runat="server"EnableViewState="False"UpdateMode="Conditional"> <ContentTemplate> <asp:GridViewID="GridView1"runat="server"AllowPaging="True" AutoGenerateColumns="False"BackColor="SteelBlue"DataKeyNames="IdeaNumber"DataSourceID="ObjectDataSource1"ForeColor="White"GridLines="None"Width="504px"AllowSorting="True"> <Columns> <asp:CommandFieldShowEditButton="True"/> <asp:BoundFieldDataField="IdeaNumber"HeaderText="IdeaNumber"InsertVisible="False" ReadOnly="True"SortExpression="IdeaNumber"/> <asp:BoundFieldDataField="IdeaName"HeaderText="IdeaName"SortExpression="IdeaName"/> <asp:CheckBoxFieldDataField="IdealDone"HeaderText="IdealDone"SortExpression="IdealDone"/> </Columns> <AlternatingRowStyleBackColor="LightBlue"ForeColor="SteelBlue"/> </asp:GridView> <asp:ObjectDataSourceID="ObjectDataSource1"runat="server"DeleteMethod="Delete" EnableViewState="False"InsertMethod="Insert"OldValuesParameterFormatString="original_{0}" SelectMethod="GetIdeaData"TypeName="IdeaDataSetTableAdapters.IdeaTableTableAdapter" UpdateMethod="Update"> <DeleteParameters> <asp:ParameterName="Original_IdeaNumber"Type="Int32"/> </DeleteParameters> <UpdateParameters> <asp:ParameterName="IdeaName"Type="String"/> <asp:ParameterName="IdealDone"Type="Boolean"/> <asp:ParameterName="Original_IdeaNumber"Type="Int32"/> </UpdateParameters> <SelectParameters> <asp:ControlParameterControlID="DropDownList1"Name="IsDone"PropertyName="SelectedValue" Type="Boolean"/> </SelectParameters> <InsertParameters> <asp:ParameterName="IdeaName"Type="String"/> <asp:ParameterName="IdealDone"Type="Boolean"/> </InsertParameters> </asp:ObjectDataSource> <asp:DropDownListID="DropDownList1"runat="server"AutoPostBack="True"> <asp:ListItemValue="false">To do</asp:ListItem> <asp:ListItemValue="true">Completed</asp:ListItem> </asp:DropDownList> </ContentTemplate> <Triggers> <asp:AsyncPostBackTriggerControlID="GridView1"EventName="RowEditing"/> </Triggers> </asp:UpdatePanel> </asp:Panel> <br/> <br/> </form></body>



well, not sure on what's happening there...anyways, i'll just leave my 2 cents. first, if you have an updatepanel, i'm not sure if you'll be wining much with the grid's paging and sorting through callbakcs (if you have the time, compare the size of each request - yeah, i believe that through callbacks you'll have less to transport but you can't do other interesting things).

second, i can't seem to think of a good reason why the callback mechanism should not working with the updatepanel partial postbacks. try using fiddler to see what's happening between client and server...

No comments:

Post a Comment