Develop Reference

What is the correct way to put multiple controls inside update panel?

I have one registration form which contains 3 to 4 dropdown controls and 2 datepickers and now when dropdown controls value are selected(selectedindex change are fired)
then i dont want my page to postback.
I have use update panel to stop this behaviour of post like below:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<%--Update Panel for date picker%>
<asp:UpdatePanel ID="UpdatePanelDatepicker" runat="server">
<ContentTemplate>
<telerik:RadDatePicker ID="rdpDate1" runat="server">
</telerik:RadDatePicker>
</ContentTemplate>
</asp:UpdatePanel>
<%--Update Panel for Dropdown--%>
<asp:UpdatePanel ID="updatepaneldata" runat="server">
<ContentTemplate>
<telerik:RadComboBox ID="ddlCountry" runat="server">
</telerik:RadComboBox>
</ContentTemplate>
</asp:UpdatePanel>
</ContentTemplate>
</asp:UpdatePanel>
So i just wanted to ask that is this correct way to put multiple controls under update panels??

Subscribe to ajax event of initializeRequest on client-side. In this event we can cancel an ajax postback if we need to.
The initializeRequest method is raised before processing of the asynchronous request starts. You can use this event to cancel a postback.
In this event, we will check if an async postback is being initiated due to ddlCountry, and if yes then we cancel the ajax post back so no post back occurs.
To solve your problem just do the following : Add following JavaScript to your aspx page. In code below, the pageLoad method is automatically called by ASP.Net Framework on client-side when browser loads the page and after all scripts have been loaded as well as all client-side objects created.
JavaScript to cancel combobox post back
<script type="text/javascript">
function pageLoad()
{
Sys.WebForms.PageRequestManager.getInstance().add_initializeRequest(CancelComboBoxPostback);
}
function CancelComboBoxPostback(sender, args)
{
var prm = Sys.WebForms.PageRequestManager.getInstance();
if (prm.get_isInAsyncPostBack() & args.get_postBackElement().id == 'ddlCountry') {
args.set_cancel(true);
}
}
</script>
The following is only a recommendation and not a part of the solution to your specific problem: Also, I would recommend to stay away from nested update panels as this can cause unexpected results if developer is not aware of how nested update panels work. In your situation, a single update panel should suffice as in markup below instead of nested update panels that you have used in your original markup.
Markup without nested update panels
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<telerik:RadDatePicker ID="rdpDate1" runat="server">
</telerik:RadDatePicker>
<telerik:RadComboBox ID="ddlCountry" runat="server">
</telerik:RadComboBox>
</ContentTemplate>
</asp:UpdatePanel>

Honestly, the UpdatePanel I find is more trouble than it is worth.
UpdatePanel controls are a central part of Ajax functionality in
ASP.NET. They are used with the ScriptManager control to enable
partial-page rendering. Partial-page rendering reduces the need for
synchronous postbacks and complete page updates when only part of the
page has to be updated. Partial-page rendering improves the user
experience because it reduces the screen flicker that occurs during a
full-page postback and improves Web page interactivity.
I often find the controls implementation causes more problems then it is worth. So I often implement my own Ajax services, to handle such logic. You can do this the old school way, quite easy.
// Create .aspx page, to be our service.
public class ControlUpdateService
{
protected void Page_Load(object sender, EventArgs e)
{
// Use an approach to determine which control type, and model to build.
// You would build your object, then use Newtonsoft.Json, to serialize, then
// return the object, via Response.End(object).
}
}
Then your page would Ajax the data, hit the service, then build your control via the .success in the Ajax call. If you do this approach, you commit to saving your data via Ajax as well. Keep that in mind. As I was answering this question, I can't help but feel your problem actually stems from the control doing an AutoPostback. Which you can actually disable.
AutoPostBack = "false";
Telerik may be different, but the documentation should clearly indicate how to disable this feature. Which would eleminate your need for an UpdatePanel all together. Allowing you to save your data, on PostBack correctly.

Use telerik Ajaxloadingpanel except UpdatePanel this is good for your code try this Example
<telerik:RadAjaxLoadingPanel ID="rlp" runat="server" Skin="Metro">
</telerik:RadAjaxLoadingPanel>
<telerik:RadAjaxPanel runat="server" LoadingPanelID="rlp" skin="Metro">
<telerik:RadDatePicker ID="rdpDate1" runat="server">
</telerik:RadDatePicker>
<telerik:RadComboBox ID="ddlCountry" runat="server">
</telerik:RadComboBox>
</telerik:RadAjaxPanel>

Modal Popup not firing in C#

I have been trying to get a Modal Popup to work for the last few months. I try and try, and after a while I just give up and find another way to work around it. I am very new to programming and have been doing some helpful things for my department, but in order to make these things viable alternatives I need to get more functionality out of them.
I want to be able to update a row in my SQL server, but the gridview is pulling data from a View, so the built in edit options won't work for me. I was hoping to be able to have a Modal Popup appear on the screen so that I can have the user put the data in and it will build the proper SQL statement to update the row.
I can't even get a Modal Popup with a single line of text to 'popup' though.
At the top of the page I have this:
<%# Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="cc1" %>
Then in my main div I have this:
<cc1:ToolkitScriptManager ID="ToolkitScriptManager1" runat=server"></cc1:ToolkitScriptManager>
Then down in the body I have this:
<asp:Button ID="btnTest" runat="server" Text="Test" />
<cc1:ModalPopExtender ID="mp1" runat="server" PopupcontrolID='pnlEdit" TargetControlID=btnTest" OkControlID="btnSubmit" CancelControlID="btnClose" BackroundCssClass="modalBackground" ></cc1:ModalPopupExtender>
<asp:Panel ID="pnlEdit" runat="server" style="display:none">
<div class="modalPopup>
<p>Text goes here.</p>
<asp:Button ID="btnSubmit" runat="sever" Text="Submit" />
<asp:Button ID="btnClose" runat="sever" Text="Close" />
</div>
</asp:Panel>
Code Behind currently has nothing for this. I have tried the same code with the variation of giving the btnTest an OnClick that does mp1.Show();. And also tried adding a "dummy" TargetControlID that is rendered but not shown in order to use the Code Behind to fire.
Every variation produces the same results. The "Test" button is clicked and then nothing happens. It appears that the page is reloaded. What am I missing here?

Please take a look at this Solution

How to change image without refreshing the page

I have a website where the user can select different cards. I need a way where when a new card is selected then the page does not refresh. When I click the back button now it just goes back to previous selections. I need it to go back to the previous page. Here is the code for the image change
<div class="imgCard" style="padding-right: 50px">
<asp:ScriptManager ID="ScriptManager" runat="server" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="conditional">
<ContentTemplate>
<fieldset style="border-width: 150px; border-style: none">
<asp:Image ID="imgCardChoice1" runat="server" />
<br />
<br />
<a id="openChange1" href="#" style="color: Red">Change Card</a>
</fieldset>
</ContentTemplate>
</asp:UpdatePanel>
</div>
When the user clicks on "Change Card" then a jquery modal box opens and allows them to change the card. Thank you for any help/advice. If needed the code behind to select a new card is in C#.

Without knowing more, it sounds like you need to use AJAX to do that. If you are already using jQuery, check out jQuery.load(). You can make an AJAX request to a url on your site that will only return the image information and load that into the element you specify.
Here is a link to the docs:
http://api.jquery.com/load/

Try to use some javascript function.
create a div where you want to put your image.
then give him an ID, on javascript function call the div id and change the src to the image that you want to put.
on your link or wathever you have to change the image, call the onclick function and use the javascript function.
On my website i have 2 images, that onmouseover change an image in other div completely different.
see it on:http://roundhillevents.com
and pass the cursor on the facebook and on the youtube logo's.
If nothing appears, let stay the cursor over that a little while.
PS: Only works with forefox and don't know why.

HTML Select items count in asp.net

Hi I've an HTML select control in my ASP.NET page and I made it as runat = "server" and now I tried to add some list items to it dynamically. something like below code
var list = document.getElementById('<%=list1.ClientID%>');
var newListItem = document.createElement('OPTION');
newListItem.text = "Emp1";
newListItem.value = "e101";
list.add(newListItem);
<asp:Panel ID="pnlemp" runat="server"
Style="display: none;"
CssClass="modalPopup"
width="700px" Height="350px">
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<select id="list1" multiple="true" name="list1" runat="server">
</select>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Panel>
and now when I try to access this from my code like list1.Items.Count it is showing 0.
Anything wrong in this?
Thanks in advance

When you modify the html in a client side script, the viewstate (which keeps track of all the controls) doesn't update . That results in that when you make a postback the new items isn't "there" .
Sometimes there's a __doPostBack() javascript which forces a postback, but I'm not sure it'll work .

For solution to this problem either add items dynamically through server side code or
dont bring server side into the picture and handle everything via javascript.
Items added via javascript will not be persisted by asp.net. further more you may recieve a "Invalid Callback or PostBack Argument" Exception for the same because it will not understand from where these listitems(options) have been added in the Select.

Search using Update Panels

Is it possible to use an UpdatePanel that has like a few text boxes, and a search button, and then perhaps another UpdatePanel that has a gridview in it to return the results of what was searched. When the user clicks search it hides the boxes, and displays the gridview. Can I do this with UpdatePanels? I am using c# for my coding. Or should I be doing this another way?

You only need one UpdatePanel in that case and setup a Trigger to your search Button.
Put only the controls that will be refreshed in your UpdatePanel.
Example:
<asp:TextBox ID="txtSearchCriteria" runat="server" />
<asp:Button ID="btnSearch" runat="server" OnClick="btnSearch_Click" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnSearch" EventName="Click" />
</Triggers>
<ContentTemplate>
<asp:GridView ID="grdSearchResults" runat="server">
</asp:GridView>
</ContentTemplate>
</asp:UpdatePanel>
Implement the btnSearch_Click function to execute your search and bind the results to the GridView. The UpdatePanel will handle the ajax call and replacing of the HTML that the GridView will produce.
You want to keep as much out of the UpdatePanel as possible and only include what will actually change because it is transmitting that HTML with each update so it's a waste of resources if you are not actually doing anything to those controls with each action. That is why a trigger is best to be used in this case which will hook the UpdatePanel to the Click event outside of the UpdatePanel scope.
Read up more on UpdatePanel and how triggers work on MSDN.

If I understand the question correctly, you can do that with two <asp:Panel> controls inside the <UpdatePanel>. One panel for the textboxes, and the other for the gridview. You set which panel to show in the codebehind, depending on whether you're expecting your user to enter search criteria, or review the search results.

Yes you can.
You also could use just one update panel. Since you the Search Form (could be in a Panel) and the GridView inside the UpdatePanel.