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Enable browser back button for repeater control with update panel in asp.net c# with master page

I have page Searchbook.aspx which have 3 dropdowns and one repeater control which have button when i navigate to another page through that button to another page .when i click the back button of browser first page get default values instead of searched values. i want to restore the searched values.

You can switch on the history of the browser for update panel requests by setting the switch EnableHistory=true in the ScriptManager.
Here is a code sample that might help...
<asp:ScriptManager ID="scm" runat="server"
EnableHistory="true"
OnNavigate="scm_Navigate"
/>
<div>
<asp:Button ID="btnSubmit" runat="server" Text="Click Me!"
onclick="btnSubmit_Click" />
<asp:UpdatePanel ID="upl" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:Label ID="lblTime" runat="server" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnSubmit" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
Here is the source: http://aspnetpodcast.com/CS11/blogs/asp.net_podcast/archive/2008/06/15/asp-net-podcast-show-116-using-the-history-functionality-with-the-asp-net-ajax-updatepanel-in-net-3-5-service-pack-1-beta-1.aspx
UPDATE
You can also use this method for adding a history point in browser.
http://msdn.microsoft.com/en-us/library/system.web.ui.scriptmanager.addhistorypoint(v=vs.100).aspx
Maybe this answer on SOF can also help...
https://stackoverflow.com/a/365746/217757
UPDATE 2
This blog post from Scott Gu sums it all...
http://weblogs.asp.net/scottgu/Tip_2F00_Trick_3A00_-Enabling-Back_2F00_Forward_2D00_Button-Support-for-ASP.NET-AJAX-UpdatePanel

If you want to restore the searched values on browser back button, then there are two ways to solve.
Keep the filter values selected by user in ViewState.
=> In this case always bind you data by implementing conditions which get from viewstate.
Or keep the values for filter data in query string.
=> In this case when user selected filter criteria put values in query string and bind data by putting condition with value fetched from URL query string.
Both above process can solve your purpose but the second one will be efficient and fast as putting values in Viewstate will slow down page.
Please let me know if I am not able to get you issue properly.
Update -
You can use Viewstate method as you are using update panel and using query string make page refresh.
Viewstate is same as using Session variable, please see below code.
Add value in viewstate
ViewState.Add("filter1", DropDownList1.SelectedValue);
Get value from viewstate
string getvalue = ViewState["filter1"].ToString();
So when after selecting filter criteria when click on submit button set value in viewstate and on page load get the same value and bind your control using those values.

Auto Fill Textbox in ASP.NET depending on the text typed in another textbox

how to fill textbox in asp.net while i am typing in another text
.. changes in one textbox will affect in another textbox auto.. and without refreshing my page.

Ok, try this. You will need the AJAX Control Toolkit. So read the article Installing AJAX Control Toolkit 4 in Visual Studio 2010 to see how to install it in Visual Studio.
Then you need to add a ScriptManager to your ASPX page. You will need to add the following code:
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
What you then need to do, is add an UpdatePanel to your page. Inside this update panel, you need to place the textbox. This means that only the controls inside the update panel will refresh, and not the whole page. To do this, add the following code:
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<!--Add your Textbox Control to update here: Textbox1-->
<asp:TextBox ID="Textbox1" runat="server" ReadOnly="True"></asp:TextBox>
<asp:TextBox ID="Textbox2" runat="server" ReadOnly="True" ontextchanged="Textbox2_TextChanged"></asp:TextBox>
</ContentTemplate>
<Triggers>
<!--This is the textbox you will be typing text into: TextBox2-->
<asp:AsyncPostBackTrigger ControlID="Textbox2" EventName="TextChanged" />
</Triggers>
</asp:UpdatePanel>
The Trigger tells your page which control on the form needs to initiate the postback. Now in your .cs file, you need to add the event handler for the Textbox2 TextChanged event. Add the following code:
protected void Textbox2_TextChanged(object sender, EventArgs e)
{
// Set the text of textbox1 = textbox2
}
I hope that this helps.

No need for AJAX. JQuery is enough. The code will do it
$('#text1').bind('keyup', function(){
$('#text2').val($('#text1').val());
});
Assuming
text1 id of box writing into.
text2 textbox that text gets copied to
in .Net you will have to use client id to get the correct id so it may look like this
$('<%=text1.ClientID%>').bind('keyup', function(){
$('<%=text2.ClientID%>').val($('#text1').val());
});
Oh and wrap it up in $(document).ready as per standard. And of coures you need to include the JQuery library to your page.
No posting back or page refreshes at all. It's your lightest solution and easy to implement.

You will need to use Javascript to accomplish this. ASP.Net code runs on the server side, which means it cannot affect the page without a postback happening first. Read up on the OnTextChanged event and how to hook into it with javascript. There is a javascript library called jQuery which makes everything easier, though it isn't strictly necessary.

Use JQuery. You may need to make an AJAX call to the server if you are relying on a datasource such as a database to autofil this field.

How to display hidden placeholder without refreshing the page?

I have two placeholders in one page and basically my requirement is that I want to show other placeholder on click of button which is in first placeholder without refreshing the page.
But when I m clicking on the button in 1st placeholder it is refreshing the page and then showing me second placeholder.I m open to hear any other suggestions also if it is not possible through placeholder.
Can anyone tell me how to achieve this?
Thanks,

You could, as suggested, use an UpdatePanel. As long as you ensure that both PlaceHolders exist within the ContentTemplate element, you will be able to switch between the PlaceHolders without the whole page being refreshed.
However, such convenience comes at the cost of control. This isn't a knock on Microsoft. The same problems exist for most ready-rolled solutions.
Whatever route you choose, you're going to need something to refresh part of the current page's DOM. And really, this means Javascript.
Do the actions in PlaceHolder 1 change the content of PlaceHolder 2? If not, you could render both, and simply use CSS to make PlaceHolder 2 invisible on load. You could then use Javascript events to make it visible as desired.
If actions on PlaceHolder 1 do affect PlaceHolder 2, then the above solution won't work, as you'll need to work out what PlaceHolder 2 is going to contain before displaying it.
The real question is whether you employ your own Javascript ( possibly in conjunction with a mature js library like mootools or jQuery ), and maybe learn something in the process, or run with the ASP .NET AJAX stuff for the quick solution, and hope you don't run into any problems.

You could wrap an updatepanel around you PlaceHolder:
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Always">
<ContentTemplate>
<asp:PlaceHolder runat="server" ID="placeholder">hello</asp:PlaceHolder>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Button1" />
</Triggers>
</asp:UpdatePanel>
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
Codebehind:
protected void Page_Load(object sender, EventArgs e)
{
placeholder.Visible = false;
}
protected void Button1_Click(object sender, EventArgs e)
{
placeholder.Visible = true;
}
This wil generate a partial postback (via AJAX), so only the content inside my updatepanel gets updated. In the <Triggers>-section, I specify that my Button will trigger the postback.

Either use an UpdatePanel control (part of the MS ajax framework) or use JavaScript. Placeholder would have to render an HTML element, and I'm not sure that it does. If it doesn't, you can use a panel instead, and then in JS do:
function show() {
var panel = document.getElementById("<%= panel2.ClientID %>");
panel.style.display = "true";
}
<asp:Button id="btn1" runat="server" OnClientClick="show();return false;" />
HTH.

UpdatePanel and Repeater render page unresponsive after post-back

I have a page with an UpdatePanel that contains a Repeater and a text box with the number of items in the repeater. When I change the value, the page is supposed to post back and redraw the Repeater with the updated number of items. This works in principle, but the page ends up frozen after post-backs and does not accept any input - in IE 8 only. It works perfectly fine in Firefox. For instance, the context menu does not appear when I right-click in controls, and I cannot enter text in text boxes.
When I take out the UpdatePanel, the page works fine, but of course refreshes on every post-back event. This is not necessarily related to the Repeater on the page. I think I am seeing this on other pages. What's the trick here?
<asp:UpdatePanel ID="uPanel" runat="server" UpdateMode="Conditional"
EnableViewState="true" ChildrenAsTriggers="true">
<ContentTemplate>
<asp:Panel ID="Panel1" runat="server" DefaultButton="btnSubmit">
<asp:TextBox ID="tbItems" runat="server" AutoPostback="true"
OnTextChanged="textchanged_Items"/>
<asp:Repeater id="rptItems" runat="server"
OnItemDataBound="repeaterItem_Databound">
<...>
</asp:Repeater>
protected void textchanged_Items(object sender, EventArgs e) {
try {
// this methods rebinds the repeater to a List after changing
// the number of items in the list
ReflowItemRepeater();
// This is not really necessary, since Databind() appears to
// cause an update. I tried it anyways.
uPanel.Update();
}
catch (Exception ex) {
ShowError(this, "Error displaying the item list.", ex, true);
}
}
I ended up removing the update panel.
One month later, different page, I am still and again fighting this. The situation is the same.
An update panel, a repeater (actually 2 nested repeaters), and a control in the repeater that fires a postback event. The server processes the event correctly and returns control, but the browser (IE8) never refreshes the update panel. The page is unresponsive, as if in some sort of dead-lock situation. I can unlock it by clicking on a button that fires another postback event (also in the update panel). But the text boxes in the panel are not clickable or editable when this happens.
Also, it happens only the first time. Once I have "freed up" the lock, or whatever it is, it will not happen again on this page, even when I repeat the exact same steps that led to it.
When this happens, the JIT debugger does not report anything.

I would actually set Triggers within your updatepanel.
I'm not sure you need to call .Update in your code behind as the updatepanel will be updated when the trigger occurs.
Try this:

My gut feeling is that it has something to do with the use of the OnTextChanged event. For kicks, try adding a button next to the text box, and reflow the repeater when the button is clicked instead. Does IE still freeze?

So I stripped this page down to the minimum and I found out what is doing it - the AjaxToolkit:CalendarExtender. If I take it out, everything works fine. Still, I would be curious to know if there is a workaround.
Here is a link to my test page. I will keep it up for a few days.
To see the issue, select "2" from the drop-down, then type something into the first quantity field and tab out. The cursor will blink in the next field, but it does not allow input. This happened in IE8, not in Firefox.
Edit: Actually, when I went back to the full page and removed the CalendarExtender, it was still not working. I do suspect that this issue has to do with controls posting back in the UpdatePanel, but I just can't pin it down. It seems seems to be one of these things where a combination of x things does not work, while any combination of (x-1) things does work.

Regarding the initial question, here's a working sample. I don't know if it's anyhow helpful, but just to make sure...
<%# Page Language="C#" %>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server"><title>Ajax Test</title></head>
<body>
<form id="form1" runat="server">
<asp:ScriptManager runat="server" />
<asp:UpdatePanel runat="server" ChildrenAsTriggers="true">
<ContentTemplate>
<asp:Label runat="server" AssociatedControlID="txtTest">
Enter 'fruit' or 'vegetables':
</asp:Label>
<asp:TextBox
runat="server" ID="txtTest" AutoPostBack="true"
OnTextChanged="Handler_Test_TextChanged"
/>
<asp:Repeater runat="server" ID="rptItems">
<HeaderTemplate><ul></HeaderTemplate>
<ItemTemplate><li><%# Container.DataItem.ToString() %></li></ItemTemplate>
<FooterTemplate></ul></FooterTemplate>
</asp:Repeater>
</ContentTemplate>
</asp:UpdatePanel>
</form>
</body>
</html>
<script runat="server">
static readonly string[] Fruit = new string[]
{ "Apples", "Oranges", "Bananas", "Pears" };
static readonly string[] Veg = new string[]
{ "Potatoes", "Carrots", "Tomatoes", "Onion" };
void Handler_Test_TextChanged(object s, EventArgs e)
{
if(txtTest.Text == "fruit") rptItems.DataSource = Fruit;
else if(txtTest.Text == "vegetables") rptItems.DataSource = Veg;
else return;
rptItems.DataBind();
}
</script>

input hidden and updatePanel (a story of ASP.NET AJAX)

How can update a input hidden inside an UpdatePanel on an AsyncPostBack?
The user click a button outside the panel. The method associated with click event update the value of the input (it has runat="server" property).
I can't update the value of this input.
I need to store a value to use in the following postback. Maybe I can use session to store this value.
Any advice?
Thank you!

Because its a postback, you might have to perform a check in the post back event and perform the update. If not, you might have to override an earlier event. See http://msdn.microsoft.com/en-us/library/dct97kc3.aspx

If you are needing to have the update panel (and its contents) updated based on the user clicking on a button which is not in the update panel, add a section to the update panel like the following:
<asp:Button ID="btnOK" runat="server"/>
<asp:UpdatePanel ID="pnlMyPanel" runat="server">
<ContentTemplate>
<!-- Content to get updated -->
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnOK" />
</Triggers>
</asp:UpdatePanel>
The triggers section in the above example tells the update panel to update if the button is clicked.

You might want to try an <asp:HiddenField> rather than an <input type='hidden' runat='server'>. I think the asp.net version is more post-back aware.

No way. The only way to update an input is to do a complete post. It's better to use the object Session.