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How would one disable an ASP.NET WebForms button when its clicked, and have it be enabled again after postback completes?

What I would like to do is be able to disable a button as soon as it pressed, perform an operation, and re-enable the button. Seemed simple enough, but my button doesn't update when I need it to. I tried an update panel, but I'm not sure if I'm using it correctly. Am I doing something wrong? Or is there a better way to achieve this?
HTML
<asp:UpdatePanel runat="server" ID="updateSubmitButton">
<ContentTemplate>
<asp:Button ID="btnSearch" CssClass="CrossoverButton" runat="server" Text="Search" OnClick="btnSearch_Click" />
</ContentTemplate>
</asp:UpdatePanel>
C#
protected void btnSearch_Click(object sender, EventArgs e)
{
btnSearch.Enabled = false;
updateContent();
// Do a lengthy operation here.
btnSearch.Enabled = true;
}

You will need to use a client side technology to disable the button. This is because when you click the button, the page does a post back to itself, which tells the server to execute btnSearch_Click. Based on your code this will
Disable the button
Update the content
Re-enable the button
all of this happens on the server. Only after the method has finished executing, does it return context to the page.
In order to disable the button on click, you'll want to try something this:
<asp:Button ID="btnSearch" CssClass="CrossoverButton" runat="server" Text="Search"
OnClientClick="this.disabled = true;"
UseSubmitBehavior="false" />
OnClientClick="this.disabled = true;"
This line registers the client click handler, to disable itself.
UseSubmitBehavior="false"
This line tells ASP.NET to include the disabled element in the form post, so the server knows which control registered the postback.
See also -- https://stackoverflow.com/a/11832053/86860

All the actions in btnSearch_Click will be performed on server. The page will not be rendered until full page lifecycle ends.
If you want to disable the button you should use javascript to do this, and then only after disabling the button make a postback to the page.

How to check whether ASP.NET button is clicked or not on page load

How can I check whether a particular button was clicked or not in ASP.NET?
I think I need to perform some operation on Page_Load. This shouldn't be entering to Button_Click event to find. Is there any way that I can find where it was clicked or not on Client Side and take it to Page_Load?

Background: Basically __EVENTTARGET and __EVENTARGUMENT , These two Hidden controls are added to the HTML source, when ever any autopostback attribute is set to true for any of the web control.
The __EVENTTARGET hidden variable will tell the server ,which control actually does the server side event firing so that the framework can fire the server side event for that control.
The __ EVENTARGUMENT variable is used to provide additional event information if needed by the application, which can be accessed in the server.
So we can easily get the control causing postback using:Request.Params.Get("__EVENTTARGET");
PROBLEM:
The method: Request.Params.Get("__EVENTTARGET"); will work for CheckBoxes, DropDownLists, LinkButtons, etc.. but this does not work for Button controls such as Buttons and ImageButtons
The Button controls and ImageButton controls does not call the __doPostBack function. Because of this, the _EVENTTARGET will always be empty. However, other controls uses javascript function __doPostBack to trigger postback.
So, I will suggest to do something as below. Add an OnClientClick property to the buttons. Also, define a hiddenField in your Markup, whose value will contain the actual button causing postback.
<asp:Button ID="Button1" runat="server" Text="Button"
OnClientClick = "SetSource(this.id)" />
<asp:ImageButton ID="ImageButton1" runat="server"
OnClientClick = "SetSource(this.id)" />
<asp:HiddenField ID="hidSourceID" runat="server" />
On the OnClientClick property of the Button and ImageButton Call the SetSource JavaScript function
<script type = "text/javascript">
function SetSource(SourceID)
{
var hidSourceID =
document.getElementById("<%=hidSourceID.ClientID%>");
hidSourceID.value = SourceID;
}
</script>
Here onwards, you can very easily check in your Page_Load as to which Control caused postback:
if (IsPostBack)
{
string CtrlName;
CtrlName=hidSourceID.Value;
}

I just got the same trouble, have to do some logic judgement in the Page_Load method to treat different event(which button was clicked).
I realize the arm to get the as the following example.
The front end aspx source code(I have many Buttons with IDs F2, F3, F6, F12.
<Button Style="display: none" ID="F2" runat="server" Text="F2:Cancel" OnClientClick="SeiGyo(this)" OnClick="F2_Click" />
<Button Style="display: none" ID="F3" runat="server" Text="F3:Return" OnClientClick="SeiGyo(this)" OnClick="F3_Click" />
<Button Style="display: none" ID="F6" runat="server" Text="F6:Run" OnClientClick="SeiGyo(this)" OnClick="F6_Click" />
<Button Style="display: none" ID="F12" runat="server" Text="F12:Finish" OnClientClick="SeiGyo(this)" OnClick="F12_Click" />
The back end aspx.cs source code, what I need to do is judge which button was clicked when Page_Load was triggered. It seems a little stupid, but works.
In your situation, the button be clicked will be added into dic. I hope that will be helpful to some one.
Dictionary<string, string> dic = new Dictionary<string, string>();
foreach(var id in new string[]{"F2","F3","F6","F12"})
{
foreach (var key in Request.Params.AllKeys)
{
if (key != null && key.ToString().Contains(id))
dic.Add(id, Request[key.ToString()].ToString());
}
}

The UniqueID of the button will be in Request.Form["__EVENTTARGET"]
This question is already answered at: ASP.NET : Check for click event in page_load

You can try using the hidden field. Make the client side event on the OnclientClick event and try setting the value of hidden field, may be true or false depending on the condition.
And on the page load you can check the value of Hiidden field.
function click()
{
// set the hidden field here
}
And on the page load, simply check the value.
if(HiddenFieldName.Value=="true")
{
//perform the action
}

private bool button1WasClicked = false;
private void button1_Click(object sender, EventArgs e)
{
button1WasClicked = true;
}
if ( button1WasClicked== false)
{
//do somthing
}

Method being triggered on page load but not via asp button

I have two asp:Labels, the first of which is replaced with a few buttons and the second with a list of items.
I want to click on the buttons to filter the items.
The contents of the buttons are added programmatically by replacing the text with html and works fine.
asp:
<form id="form1" runat="server">
<asp:Label id="filters" runat="server" Text="Filters here"/>
<asp:Label id="itemList" runat="server" Text="List of items here"/>
</form>
resultant html of filters label:
<input type="submit" onclientclick="Load_Items(0)" runat="server" value="First"/>
<input type="submit" onclientclick="Load_Items(1)" runat="server" value="Second"/>
<input type="submit" onclientclick="Load_Items(2)" runat="server" value="Third"/>
relevant c#:
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
Load_Items(0);
}
}
public void Load_Items(int filterType)
{
//code to load items (pseudo below)
for each row in list
if filterType = itemType
build string
replace second label with string
}
On page load everything happens just as I want it to with the contents being filtered by the first item (hence Load_Items(0)), and if I manually change the 0 to another number in Page_Load, it filters by the other types, but if I click the buttons which are programmatically added, nothing happens other than what looks like the page refreshing.
I know the post back check is working by adding a text replacement before and inside it.
I've also added an asp:button to make sure it's not something to do with the way the buttons are added as below (with some extra things recommended from searches):
<asp:Button runat="server" CausesValidation="False" onclientclick="Load_Items(2); return false;" text="Submit" />
So what could be the issue?

The OnClientClick property specifies the javascript to run in the browser when the button is clicked. Since you probably don't have a javascript function called Load_Items, this will generate a script error, and the button will then cause the form to post back.
The server-side Click event will fire on the server, but doesn't allow you to pass a parameter. You will only get the button instance and an empty EventArgs instance.
You might be better off using the Command event, combined with the CommandArgument property.
<asp:Button runat="server" CommandArgument="2" OnCommand="Load_Items" ...
The event handler would use the CommandArgument property of the CommandEventArgs to access the argument from the clicked button:
protected void Load_Items(object sender, CommandEventArgs e)
{
Load_Items(Convert.ToInt32(e.CommandArgument));
}

Well, that's the common problem which I think every asp.net developer deals some time. The common part of it, that asp.net event system doesn't work, as windows forms.
Page object, and all controls on that page, have lifecycle events, that are triggered during any request, even when it's from update panel.
As you create those controls by code, you have to keep in mind, that all events for those controls should work as part of Page object. That's why you have to create those object in Page_Init event, before all other control's event would be triggered.
Please also keep in mind that you have to create those controls as asp.net objects:
var btn = new Button();
But not by simply adding html markup. And you have to recreate them on each request, following that one, when they were created.
Please take a look on my another answer.

Redirecting to new page ASP.NET

I am having trouble trying to redirect to a new page after the button has been clicked. But this button also saves my datatable into an excel file. I want it to be able to save and redirect at the same time.
this is the code in the .CS file for the button
protected void SaveButton_Click(object sender, EventArgs e)
{
this.SaveExcel();
Response.Redirect("Default.aspx", true);
}
Also in the .aspx page i have this
<asp:Button ID="SaveButton" runat="server" Text="Save"
onclick="SaveButton_Click" Enabled="False" onclientclick="needToConfirm=false"/>
as you can see i have a onlclientclick function which is needed.
I have tried using javascript and also the Server.Transfer metothds. Has anyone got an idea how to do this?

Your OnClientClick should be in the following format.
OnClientClick="needToConfirm(); return false"
If this doesn't work there is an error in your JavaScript which is causing your c# code not to fire.

Click Event of Hyperlink

How to find Whether a hyperlink is clicked or not in ASP.net C# in runtime?
I want to write code on like that
Response.Redirect("Default.aspx");

If you want to execute server code upon a click in a link, then you should use the ASP.NET control <asp:LinkButton>
This is just like a button and will allow you to hook up Server Side Events and at the end you can just redirect the viewer to any page.

You would attach either the event in the code behind, or in the ASPX / ASCX of your link in question like so:
<asp:LinkButton ID="linkGoSomewhere" runat="server" Click="linkGoSomewhere_Click" />
OR
linkGoSomewhere.Click += (linkGoSomewhere_Click);
With an event handler looking like so in your code:
public void linkGoSomewhere_Click(object sender, EventArgs e)
{
Response.Redirect("Default.aspx");
}
HOWEVER
In this situation, you don't need a server side control to just send the user somewhere else. You just need a simple hyperlink:
Go somewhere else

if this HyperLink you can do it using javascript but if it is LinkButton you can do it inside onclick event
<asp:LinkButton ID="MyLnkButton" runat="server" onClick="MyLnkButton_Click" Text="Click Me!">
protected void MyLnkButton_Click(Object sender,EventArgs e)
{
Response.Redirect("Default.aspx");
}

The onclick server side handler can be added to achieve this.
<asp:LinkButton ID="LinkEditLine" runat="server" Text="Edit" onclick="lnkEdit_Click"/>

You can determine this with the Click event of the LinkButton