I have an html button, see below. When it's clicked and AutoEventWireup="true", the Save_Click click handler is fired twice. When AutoEventWireup="False", it fires once.
Why is it firing twice? The button is not registered twice and no code which is adding the event handler. Using master page and no Ajax.
<button id="Save" accesskey="v" type="submit" runat="server" onserverclick="Save_Click"></button>
And now (at least in .net 4) even better:
<button runat="server">
by default behaves as it has type="submit" (fires twice on click), so for it to work correctly, we should explicitly set type="button", i.e.:
<button id="ButtonSubscribe2" runat="server" type="button" onserverclick="Save_Click"></button>
Ok I found out that that an HTMLButton fires for the onserverclick event and for the type="submit". When I removed type="submit", it fires once. This quirky behavior took me a long time to discover!
Just a guess: the handler isn't being fired twice, but you've set up a similar behavior in the Page_Load event that makes it appear to be firing twice.
Related
I'm trying to disable an asp button when it is clicked on the client side.
<asp:Button runat="server" ID="btnSubmit" Text="Save" class="Button" OnClick="btnSubmit_Click" CausesValidation="false"></asp:Button>
<script type="text/javascript">
$("input[type=submit],button").click(function (){$(this).attr("disabled", "disabled");});
</script>
when the button is clicked it does post back to the page_load , but it won't go to the btnSubmit_Click method. If I remove the jquery that disables the button it makes it from the page_load to the btnSubmit_Click method.
It seems when the button is disabled from the jquery it is no longer able to wire up to its event. Anyone have any ideas how I can disable the button client side, and still make it to the specific onclick event method?
This is resolved (Yuriy answered), the issue was that I needed to put the disabled code within the form.submit client side code. If not the disabled button was not firing its click event, yet it was still posting back, just not going to the onclick method.
solution:
$('#Form1').submit(function(){ $("input[type=submit],button").click(function (){$(this).attr("disabled", "disabled");});
I have the following code in my aspx file:
<button type="button" id="btnAskQuestion" runat="server" onserverclick="btnAskQuestion_Click">Ask Question</button>
I've tried every combination of onclick="return false;" and onclick="preventDefault()" I can think of, including putting them in the javascript function that gets called. Everything I try has one of two results: either I get a postback, or the server side code (btnAskQuestion_Click) never executes.
Any idea what I might be doing wrong?
You cannot execute server-side code this way, using onserverclick causes postback.
If you wish to prevent full page refresh and still execute server-side code, you have to call a client-side JS function via onclick and execute an AJAX call from there.
Another alternative is to use your button as a trigger for UpdatePanel - this way only partial postback will be performed.
Try using the property UseSubmitBehavior="false" in the button markup.
or you can use a "trick" :
Markup
<button onclick="myFunction()">Click Me!</button>
<div style="display:none">
<asp:Button runat="server" id="btnButton" .../>
</div>
js
function myFunction()
{
if (true statement)
$("[id$=btnButton]").click();
else
alert("false");
}
What this does is that you handle stuff with normal markup and do the logic using js. And you can trigger a click of the button that do something in the server.
There're OnClick, that fires on server and OnClientClick that fires on client browser. You should do this:
<asp:Button ID="btnAskQuestion" runat="server"
OnClick="btnAskQuestion_Click"
OnClientClick="return myfunction();">Ask Question</asp:button>
If myFunction returns true, then you will have a postback to the server.
My answer is appropriate only for ASP:Button, not the button control you are working with. Given the choice, I'd switch to ASP:Button.
You're looking for OnClientClick. If you put your JavaScript code there, it will kill the PostBack before it can hit the server.
On the other hand, if you're looking to execute server code without a PostBack, that's impossible. The PostBack is what triggers the server to act.
I have a asp.net button and I am using OnclientClick to close the window
<asp:Button ID="btnCancelSomething" runat="server" class="type-button"
Text="Cancel" OnClientClick = "Javascript:self.close()"
onclick="btnCancelSomething_Click"/>
the onclick event does nothing and I am planning to remove it. However, when I click the button the first time it is loading the page again. I click the button again then the script is fired.
How to make the window close the first time?
If the button isn't going to have any server-side functionality behind it anyway, why make it an asp:Button at all? A regular button will do the trick just fine:
<input type="button" value="Cancel" class="type-button" onclick="self.close()" />
That way it's purely client-side, since that's all the functionality that's needed anyway. It won't cause any "post-back" unnecessarily.
You could even take it a step further and break apart markup from functionality:
<input type="button" value="Cancel" class="type-button" id="cancelButton" />
Then in a script tag elsewhere, or in a separate file:
$('#cancelButton').click(function() {
self.close();
});
(Of course, this example assumes jQuery. But then what doesn't? The separation of markup and functionality if the key point here, though. How you achieve it, even how you identify the element with an id as in my example or some other way, is up to you.)
If I click a button very fast after page load, the post back won't be fired. The following example illustrates this (you have to click the button twice and very fast):
<form id="form1" runat="server">
<div>
<span id="submitText"></span>
<br />
<asp:Button ID="btnSubmitTest" runat="server" Text="Button"
OnClientClick="document.getElementById('submitText').innerText='you should not see this after postback';" />
</div>
</form>
The submitText, the button set's before firing, should not be visible after the postback. But if you click at the button very fast, it happens, that the event doesn't fire.
I think, that the page isn't loaded completely at this moment. Or is there any other reason for that behaviour? How do you handle this?
You will loose all javascript dom updates on postback. What you have explained sounds correct... you see the client click event fire just before page posts back and the dom is reset.
Try the same exercise by populating a textbox. In that instance the value will maintain as the textbox relies on viewstate. You could put a runat="server" on the span, but I believe you would have to manually assign the value to viewstate as I don't believe htmlgenericcontrols automatically utilize viewstate.
I have some simple javascript that I'd like to run when a button is clicked, but I also want some postback action to occur on the server. The logical code for this looks like this:
<asp:Button ID="btnOK" runat="server" Text="Save Changes" OnClientClick="UpdateParent();" OnClick="btnOK_Click" />
<asp:Button ID="btnCancel" runat="server" Text="Cancel" OnClientClick="window.close();" />
<script language="javascript" type="text/javascript">
function UpdateParent()
{
window.opener.document.location.reload(true); // or should we postback instead?
window.close();
}
</script>
Basically, a popup window should refresh its parent and then close itself. However... if I call window.close(), the postback does not occur and the button handler is not called. But obviously OnClientClick is called before the postback happens. Am I going to have to emit this javascript in the button handler and run it when the page loads after postback? If so, what is the proper way to do this these days for ASP.NET 2.0?
It's a shame that the code above doesn't work as it's elegantly simple and straightforward.
You have to do the postback before closing the window. Also you want to do the postback before refreshing the parent window, as I guess that the reason to refresh the window is to display the information that you are about to save.
Use the RegisterStartupScript in the ClientScript object to run the code after postback:
Page.ClientScript.RegisterStartupScript(this.GetType(), "close", "window.opener.location.reload(true);window.close();", true);
However, if the parent page is a result of a postback, this would cause a dialog window in the browser informing the user that a post request is needed to reload the page. To avoid this you would have to do something like calling a function in the parent page that could do a postback to update the page.