AJAX postback disable

[Roman Krsko]

Hi,

I have problem with ajax postback. Is possible to cancel ajax postback after refresh grid.

I have grid and I use this code:

function RefreshGrid(search) {
  if (search != "") {
    document.getElementById("search").value = search;
    var masterTable = $find("<%= grdResult.ClientID %>").get_masterTableView();
    masterTable.rebind();
  }
}

function requestStart(sender, eventArgs) {
     document.getElementById("ajaxrequest").value = "true";
}
function responseEnd(sender, eventArgs) {
    document.getElementById("ajaxrequest").value = "false";
}

But problem is, that I refresh grid, all page codebehind are called. Not only webservice (use it for reading data).
In PageLoad I use

sAjaxRequest = Request.Params["ajaxrequest"] + "";
if (sAjaxRequest != "true")
{
     //... loading controls and set property from DB (radcombo, radgrid, ...)
}

Grid

<telerik:RadGrid ID="grdResult" runat="server" AllowPaging="True" AllowSorting="True" AutoGenerateColumns="False" GridLines="None" onitemdatabound="grdResult_ItemDataBound" PageSize="20" Width="100%" DataSourceID="GridDataSource" BorderStyle="None">
 <PagerStyle Mode="NextPrevAndNumeric" PageButtonCount="10" />
   <ClientSettings AllowDragToGroup="True" EnableRowHoverStyle="true">
   <DataBinding EnableCaching="true" />
   <Selecting AllowRowSelect="true" />
   <ClientEvents /></ClientSettings>
   <HeaderContextMenu enableautoscroll="True"></HeaderContextMenu>
   <MasterTableView>
      <Columns>
         <telerik:GridBoundColumn DataField="Manufacturer" HeaderText="Manufacturer" UniqueName="colManufacturer"></telerik:GridBoundColumn>
         <telerik:GridBoundColumn DataField="Stock" DataFormatString="{0:0}" HeaderStyle-HorizontalAlign="Right" HeaderText="Stock" ItemStyle-HorizontalAlign="Right" UniqueName="Stock"></telerik:GridBoundColumn>
         <telerik:GridBoundColumn DataField="Price" HeaderStyle-HorizontalAlign="Right" HeaderText="Price" ItemStyle-HorizontalAlign="Right" UniqueName="Price"></telerik:GridBoundColumn>
        </Columns>
      </MasterTableView>
</telerik:RadGrid>
<asp:ObjectDataSource ID="GridDataSource" runat="server" SelectMethod="FillResultGrid" TypeName="shop.Service">
  <SelectParameters>
    <asp:FormParameter FormField="search" Name="sSearch" Type="String" />
  </SelectParameters>
</asp:ObjectDataSource>

Problem is, that I don't set combos data and property, then I receive blank controls after ajax.
Ajax framework set my controls, but I don't want it.

Thanks for answer.
Roman Krsko

[Iana Tsolova]

Hello Roman,

The main difference between regular postback and ajax callback is that only part of the page html is send back on the client after ajax request. However you should note that the page lifecycle is executed the same way with postback or callback.
Thus if you are using a web service for extracting data, I would suggest that you consider binding the RadGrid client-side. Find the below online demos for a reference:

http://demos.telerik.com/aspnet-ajax/grid/examples/client/livedata/defaultcs.aspx
http://demos.telerik.com/aspnet-ajax/grid/examples/client/declarativedatabinding/defaultcs.aspx

Best wishes,
Iana
the Telerik team

[Roman Krsko]

Hi,

I try this samples, but I don't know, how to use it. I receive always error code
Error: Sys.ArgumentException: Cannot deserialize. The data does not correspond to valid JSON.
Parameter name: data
Source file : http://localhost/webshop/Telerik.Web.UI.WebResource.axd?_TSM_HiddenField_=radScriptManager_TSM&compress=1&_TSM_CombinedScripts_= %3b%3bSystem.Web.Extensions%2c+Version%3d3.5.0.0%2c+Culture%3dneutral%2c+PublicKeyToken%3d31bf3856ad364e35%3aen-US%3ad0c ...

This is webservice code

[WebMethod(EnableSession = true)]
public DataSet FillResultGrid()
{
  try
  {
     DataSet dsSearch = new DataSet();
     ...
     return dsSearch;
  }
  catch { ... }
}

This is code of grid

<telerik:RadGrid ID="grdResult" runat="server" AllowPaging="True" AllowSorting="True" AutoGenerateColumns="False" GridLines="None" PageSize="20" Width="100%" BorderStyle="None">
 <PagerStyle Mode="NextPrevAndNumeric" PageButtonCount="10" />
   <MasterTableView>
      <Columns>
         <telerik:GridBoundColumn DataField="Manufacturer" HeaderText="Manufacturer" UniqueName="colManufacturer"></telerik:GridBoundColumn>
         <telerik:GridBoundColumn DataField="Stock" DataFormatString="{0:0}" HeaderStyle-HorizontalAlign="Right" HeaderText="Stock" ItemStyle-HorizontalAlign="Right" UniqueName="Stock"></telerik:GridBoundColumn>
         <telerik:GridBoundColumn DataField="Price" HeaderStyle-HorizontalAlign="Right" HeaderText="Price" ItemStyle-HorizontalAlign="Right" UniqueName="Price"></telerik:GridBoundColumn>
        </Columns>
      </MasterTableView>
      <ClientSettings EnableRowHoverStyle="true">
         <Selecting AllowRowSelect="true" />
         <DataBinding EnableCaching="true" Location="~/WebshopService.asmx" SelectMethod="FillResultGrid" />
         <ClientEvents OnDataBinding="grdResult_DataBinding" />
       </ClientSettings>
</telerik:RadGrid>

What I do bad?
Thanks for answer.

Roman

[Iana Tsolova]

Hello Roman,

Try modifying the FillResultGrid method so it returns Dictionary object as the GetDataAndCount() method from the attached WebService and see if it makes any difference? Note that the same WebService is used for the second RadGrid data-binding in this demo.

Greetings,
Iana
the Telerik team

[Roman Krsko]

Hello Lana,

I copied my sample to the demo project, and it was running successful.
Trying run the same sample in my project I still receive the posted error.
Trying to copy a telerik sample into my project fails also.
I'm not sure missing an entry in the Web.config.

Roman

[Iana Tsolova]

Hello Roman,

Based on the provided information so far I am not sure what could have gone wrong in your case. Therefore I suggest that you open a formal support ticket and either send us a runnable project or at least the problematic pages, and code files for further research.

Sincerely yours,
Iana
the Telerik team

[Roman Krsko]

Hi Lana,

thanks for your help, I solve this problem.
Problem was, that inside grid is default property DataBinding-CountPropertyName set as  "Count" and DataBinding-DataPropertyName="Data", but this is not visible inside aspx and I use own names.

But I have another question. Is possible use other means of fill data as list of objects? For example DataSet or XML for Client-side databinding. Or can I use xml and then transform with javascript to necessary structures.
Both two samples (Client-side databinding) are only with list of objects, but I need something dynamically (XML, DataSet).
Thanks.

Roman

[Iana Tsolova]

Hello Roman,

If you want to bind the grid to Xml, I would suggest that you use server-side binding.
Otherwise you can consider implementing your scenario in MVC.

Best wishes,
Iana
the Telerik team