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C# ASP.NET CheckBox in UpdatePanel does not register click when clicked "during" update

Everything works as it should. I just find it annyoing that if you manage to click the checkbox "during" the update of the updatepanel it does not grab the click. Is there som workaround/fix for this or do I simply have to rethink my design and put the checkboxes in a different panel?

If you use AutoPostBack="True", checkbox will be working fine. Thanks
<asp:UpdatePanel ID="updatepanel" runat="server">
<ContentTemplate>
<asp:Checkbox ID="chk" runat="server" AutoPostBack="true"></asp:CheckBox>
</ContentTemplate>
</asp:UpdatePanel>

Your logic update shouldn't be on the same thread/task of the View (except some cases). Look for "c# async", you will find everything you need in Internet.

How to implement a click event on textbox in ASP.NET?

In my web application I need a functionality so that when users click on textbox to input values, it should make the button and the other fields visible?
I am using the code provided below but, could not get it working.
C#:
protected void TextBox1_Click(object sender, EventArgs e)
{
ButtonSearch.Visible = true;
}
ASP.NET:
<asp:TextBox ID="TextBox1" runat="server" OnTextChanged="TextBox1_TextChanged" OnClick="TextBox1_Click"></asp:TextBox>
<asp:Button ID="ButtonSearch" runat="server" OnClick="ButtonSearch_Click" Text="Search" Visible="False" />
How to accomplish this?

Set AutoPostback="True". This way the event will be fired server-side, and the button will become visible.
<asp:TextBox ID="TextBox1" runat="server" OnTextChanged="TextBox1_TextChanged" OnClick="TextBox1_Click" AutoPostBack="true"></asp:TextBox>
However, if you only want to toogle visility of a button, you really should considerate javascript. This will save a trip back to the server.
<asp:TextBox onclick="txtBox1_ClientClicked()" ID="TextBox1" runat="server" OnClick="TextBox1_Click"></asp:TextBox>
<asp:Button ID="ButtonSearch" runat="server" OnClick="ButtonSearch_Click" Text="Search" style="display:none;" />
<script type="text/javascript">
function txtBox1_ClientClicked(){
var theButton = document.getElementById('<%=ButtonSearch.ClientID%>');
theButton.style.display = 'block';
}
</script>

You do not need to post back to the server to accomplish your job. You can use client side onFocus event and javascript/jquery, for example.
I know I used an input of type text, and you are using an ASP Control which posts on server, but here is a JSFiddle to get you on the right track: http://jsfiddle.net/Mmjtz/1/

$("<%= ButtonSearch.ClientID %>").click(function(){
$("#TextBox1").show():
});
In this code you need to pass fields ID which you want to visible on the click of button.

Put the textbox inside a div and use the div's onClick event from codebehind. It's not what you asked but it works for me without any errors. Here is a javascript function to implement requested event:
function toggleVisibility()
{
document.getElementById('TextBox1').disabled = true;
/*
...some other code...
*/
}
And of course, you have to define your onclick event at the div definition after implementing this JS function.
<div id="TBdiv" onClick="toggleVisibility()">
<asp:TextBox ID="TextBox1"..../>
</div>
IMPORTANT: Since you now disabled your TextBox from codebehind, you have to enable it in somewhere before you want to use it again. Otherwise you will not see it while the page is running.

jQuery is the perfect solution for your problem. The code would be something like this:
$("#TextBox1").on("click",function(){$("#ButtonSearch").css("visibility", "visible");})
You include the script by adding <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script> to the page and then you can add the piece of code above to within <script></script> tags.

CodeMirror with UpdatePanel in asp.net

I'm using CodeMirror in an ASP.NET web application. The web app uses UpdatePanel (ajax).
In ajax postback, I'm not able to get updated text from the CodeMirror textbox on server side and after the postback, the text gets reset. This WORKS if I don't use an update panel. What am I missing?
Below is the code mirror code:
editor = CodeMirror.fromTextArea(document.getElementById("<%=txtLua.ClientID%>"), {
matchBrackets: true,
theme: "neat",
pollInterval: 100,
continuousScanning: 500
});
<asp:UpdatePanel ID="upd" runat="server">
<ContentTemplate>
<asp:TextBox runat="server" ID="txtLua" Height="320" Width="600" TextMode="MultiLine"></asp:TextBox>
<asp:Button ID="btn" runat="server" OnClick="btn_Click" Text="btn" />
</ContentTemplate>
</asp:UpdatePanel>
Is there an asp.net/C# sample for using CodeMirror? Any help is appreciated.

The short answer is: create a javascript event hook that fires early (before the UpdatePanel begins to do its work) and manually calls CodeMirror's .save() function.
The problem seems to arise because the auto-magic form.submit override that CodeMirror supplies is triggered after the ScriptManager has already passed the ViewState of the panel back to the server. This means the server only receives the TextBox in its initial state (CodeMirror hasn't put what you've typed into it yet). I checked the DOM events in Chrome and ScriptManager's hook was consistently ahead of the form.submit override that CodeMirror added.
I got around this by adding an .onclick to the submit button right after CodeMirror loaded. Using your example:
var editor = CodeMirror.fromTextArea(document.getElementById("<%=txtLua.ClientID%>"), {
leaveSubmitMethodAlone: true, //since you don't need this anymore, no reason to complicate your DOM
matchBrackets: true,
theme: "neat",
pollInterval: 100,
continuousScanning: 500
});
window['cmLocalStateEvent'] = function () { editor.save(); };
//saveButton = document.getElementById("<%=btn.ClientID%>"); //grab the save button
//if (saveButton) {
// saveButton.onclick = function () { editor.save(); }; //make it do what the submit action was going to do
//}
<asp:UpdatePanel ID="upd" runat="server">
<ContentTemplate>
<asp:TextBox runat="server" ID="txtLua" Height="320" Width="600" TextMode="MultiLine"></asp:TextBox>
<asp:Button ID="btn" runat="server" OnClientClick="if(window['cmLocalStateEvent'])window.cmLocalStateEvent();" OnClick="btn_Click" Text="btn" />
</ContentTemplate>
</asp:UpdatePanel>
Now the .onclick is ahead of the ScriptManager hook, and will fire first. Infact, if you put an OnTextChanged= and AutoPostBack= on the TextBox it'll fire even before the button that you just clicked does.
Essentially, the trick is to get CodeMirror's save to apply before ScriptManager submits the ViewState back to the server.
EDIT:
I've found since posting this, that you'll run into a troublesome issue if your submit button is also inside the UpdatePanel (which yours is). The .onclick will not persist after the initial submit and you'll be reset to a clean button with no event hooks. My current working solution to that scenario is adding a window['cmLocalSaveEvent'] function and adding the client .onclick to the ASP template (so the panel refresh puts it back for you). Updated code above to reflect this.

This is how I managed to make it work, just in case someone else needs it. After instantiating editor, I'm keeping the textbox aligned every time the blur event occurs.
editor.on('blur', function () {
arguments[0].save();
});

Is it possible to re-execute javascript in an UpdatePanel?

I have the following:
<asp:UpdatePanel ID="upd" runat="server">
<ContentTemplate>
<script> alert("execute again"); </script>
<asp:LinkButton ID="go" runat="server" Text="Exec JS" />
</ContentTemplate>
</asp:UpdatePanel>
The first time the page renders the script is executed. If I click the button to cause a postback it doesn't execute again.
Is there a way to make it execute the scripts again?

Yo! There's an easy way to get the JavaScript to run again. Put the javascript on the HeadContent portion of your page:
<script>
function BindIt()
{
alert("execute again");
}
</script>
then on your page inside the update panel add portion with a call up to the function that you created for your javascript:
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<script type="text/javascript">
Sys.Application.add_load(BindIt);
</script>
...
In a project that I was working on, I wanted all of the javascript on the page to run again, so I just put it all into a massive BindIt style function. It took me a while to figure it out and I tried many methods to get this to work but this was the only way I was ever able to get jquery to work with updatepanels

Since ASP is just pushing the raw data, not actually executing it you'll need to probably use the RegisterStartupScript method of the ScriptManager to programmatically inject the script to load after a partial postback.
EDIT
More directly, try looking in to ScriptManager.RegisterStartupScript() for UpdatePanels. e.g.

If the JavaScript is jQuery related, following link would definitely help:
http://weblogs.asp.net/hajan/archive/2010/10/07/make-them-to-love-each-other-asp-net-ajax-updatepanels-amp-javascript-jquery-functions.aspx
I have personally used the 2nd method mentioned in this article, and it worked for me properly.

AJAX UpdatePanel help needed

I have the following ASPX code:
<asp:ScriptManager ID="ScriptManager1" runat="server" />
<asp:UpdatePanel runat="server" ID="UpdatePanel" UpdateMode="Conditional">
<ContentTemplate>
<asp:Button runat="server" ID="UpdateButton1" OnClick="NextImg_Click" Text="Update" />
<asp:Repeater runat="server" ID="urlsUpdateRepeater">
<ItemTemplate>
<!-- THIS WOULD BE A LOOP FROM HERE -->
<!-- OPENS RESULT ITEM DIV CONTAINER -->
<div id="result_item">
<a href="<%# Eval("myUrl") %>" target="_blank">
<%# Eval("urlPageTitle")%></a>
</ItemTemplate>
</asp:Repeater>
</ContentTemplate>
</asp:UpdatePanel>
I have a NextImg_Click() event which works fine.
I use this code for DataBind... what is the Update method?
urlsUpdateRepeater.DataSource = resultsCollection;
urlsUpdateRepeater.DataBind();
Everything would appear to be in order. But every time the Update button is clicked it re-renders the whole page instead of the partial-postback UpdatePanel only.
It is driving me completely mad as I can't see anything wrong with the code. Is there some simple thing I'm missing?! Please help!
The search and data is displayed correctly (inside the panel) it just will not do a partial postback.
Appreciate your help with my noob problems!

Because the button is inside your UpdatePanel's ContentTemplate, it is unnecessary to take any extra action to get a partial page postback.
Try removing the line from your Page_Load() method.

Taken from MSDN:
Use the RegisterAsyncPostBackControl
method to register controls outside an
UpdatePanel control as triggers for
asynchronous postbacks, and to
potentially update the content of an
update panel. To update an UpdatePanel
control programmatically, call the
Update method.
So, you're control (UpdateButton1) is inside the UpdatePanel, no need for the ScriptManager1.RegisterAsyncPostBackControl call - ditch it and your problem is solved.

The problem was that my <form> tag was nested further into the document than it's corresponding end tag (with Warning!)...
Upon moving my form tag - it worked!
Entirely my fault, thanks guys.