I have a problem with the following code in an ASPX page:
<script type="text/javascript">
$(document).ready(function() {
$('.test').click(function() {
alert("click")
})
});
</script>
<asp:CheckBox runat="server" Text="Checkbox XYZ" CssClass="test" ID="cb1" />
In the browser (FF3.5 / IE8) I have the following problem:
if I click the checkbox (the small square), it works as expected
if I click the checkbox's text ("Checkbox XYZ"), then the click event is fired twice, and the alert is shown twice.
I guess this has to do with the way the checkbox is rendered to HTML, which is like this:
<span class="test">
<input id="ctl00_c1_cb1" type="checkbox" name="ctl00$c1$cb1" checked="checked"/>
<label for="ctl00_c1_cb1">Checkbox XYZ</label>
</span>
How do I correctly setup the click event handler to prevent it from being called twice?
I have just experienced the same thing, but am not sure that event bubbling is causing my issue. I have a custom tree control, and when an item is opened, I use $(id).click() to attach a handler to all elements of a certain kind.
I suspect that this means that existing items elsewhere that already have the event, may then have it added again. I found that unbinding everything then re-binding solved my problem, thus:
$('img.load_expand').unbind("click").click(function()
{
// handler
});
I think it's because a <label> with a for attribute raises the click event of <input type="radio"> or <input type="checkbox"> element that is associated for when clicked.
So in your jQuery code, you set up a click event handler for both the <label> and the <input> inside <span class="test">. When clicking on the <label>, the click event handler that you set up on the label will execute, then the click event handler set up on the <input> will execute when the label raises the click event on the <input>.
$(document).ready(function() {
$('.test').click(function(event) {
event.stopImmediatePropagation();
alert("Click");
})
}
);
I was able to get my code working by stopping the event Propagation. It did not affect the status change of the checkbox.
Well after reading my question again, I found a way how to solve it.
Just add "input" to the jQuery selector:
<script type="text/javascript">
$(document).ready(function() {
$('.test input').click(function() {
alert("click")
})
});
</script>
Just use .mouseup rather than .click
What you are seeing is event bubbling. The click event is first handled by the label and is then passed on to the checkbox. You get one alert for each. To prevent event bubbling you need to return false in your click handler.
$(document).ready(function() {
$('.test').click(function() {
alert("Click");
return false;
})
});
However while this prevents event bubbling it also has the undesirable side effect of preventing the checkbox from changing state. So you'll need to code around that.
Solved: this to work with Firefox 3.6.12 and IE8.
$(function(){
$("form input:checkbox").unbind("click")
.click(function(){
val = $(this).val();
alert(val);
})
}
The trick is to unbind("click"). before bind it to .click(fn); this will disabled the same event to fire twice.
Note that event "change" will not tricker at first time checkbox has been checked. So I use "click" instead.
I ran into the same issue with a click event, and found this article. In essence, if you have more than one jQuery document-ready functions inside the
<body></body>
tags, you can get multiple events. The fix is, of course, to not do that, or to unbind the click event and rebind it, as noted above. Sometimes, with multiple javascript libraries, it can be hard to avoid multiple document.ready()'s, so the unbind is a good workaround.
<code>
$('#my-div-id').unbind("click").click(function()
{
alert('only click once!');
}
</code>
I know the question is far closed now, but I just have faced the same problem and I want to add the solution I found, may come in handy for similar problems on the future.
When you add ASP code like:
<asp:CheckBox runat="server" Text="Checkbox XYZ" CssClass="test" ID="cb1" />
the problem is that <asp:CheckBox ...> is not an html control, it's just something ASP made up from the twisted mind of some psycho invented, so the browser will receive something else.
The browser will receive something like:
<span class="test">
<input id="garbageforYourId_cb1" type="checkbox" name="garbage$moregarbage$cb1"/>
<label for="evenMoreGarbage_cb1">Checkbox XYZ</label>
</span>
One of many possible solutions:
The browser receive a span which content an input "checkbox" and a label for it with your text. Therefore my solution for this would be something like:
$('.test > :checkbox').click(function() {
if ($(this).attr("checked")) {
alert("checked!!!");
} else {
alert("non checked!!!");
}
});
What happened up there? This selector $('.test > :checkbox') means: find the elements with the class "test" and bring any checkbox that it contains.
The function runs twice. Once from the inside and then it gets called again from inside itself. Simple add a return statement at the end.
<script type="text/javascript">
$(document).ready(function() {
$('.test').click(function() {
alert("click");
return false;
})
});
</script>
<asp:CheckBox runat="server" Text="Checkbox XYZ" CssClass="test" ID="cb1" />
This worked perfectly for me.
I had the same problem with the selector. And end up using off() function.
$('body').off('click').on('click', '<your selector>', function(){
// Your code
});
Related
i m working on simple asp.net and in that i am using validators.
my situation is like that i have used reaquired field validator its working fine.
and after that if i ented data and fired insert query then data is inserted and sucessful message is displyed on the lable. but agin if i clik on submit button with empty fields then validator works but the lable of successful message does not disapper. how to hide that lable.
You need to use javascript to hide the success message, here is a sample
<script type="text/javascript">
function hide() {
document.getElementById('<%=lblSuccess.ClientID %>').style.display = 'none';
return false;
}
</script>
<asp:Label ID="lblSuccess" runat="server" Text="Success"></asp:Label>
..your form code
<asp:Button ID="btnOk" runat="server" Text="OK" OnClientClick="hide()" ValidationGroup="ValidateForm" />
Why javascript, the form doesn't get posted because validators don't let the form to be posted if the conditions aren't met, so you are left to hide the message dynamically with javascript
<script type="text/javascript">
function Hide() {
document.getElementById("Lable1").style.display = 'none';
return false;
}
</script>
<asp:Button ID="Button1" OnClientClick="Hide()" runat="server" onclick="Button1_Click" Text="Button"/>
and use
if (Page.IsValid){}
on clik event.
Show us some code of what you're up to and we can tell you more precisely where you are going wrong. In a nutshell though the visibility of that message is going to be persisted through a postback so you have to explicitly tell it to not be visible if validation has failed.
Set the label to visable=false and on save set the text value if required and change visible =true ?
On form load, do something like this:
TheValidMessageLabel.Visible = Page.IsValid;
You are probably just setting the visible state to true when it's valid and never setting it to false again.
Set your success label visibility in page load to false.
And only if operation is successfully set that label visibility to true.
cheers
I have a image button in a page which can be triggered on mouse click, by default it gets triggered on enter press also which i want to disable.
I know about "UseSubmitBehaviour" attribute in asp:Button, is there a way to do the same in asp:ImageButton?
I will assume you have some sort of input controls and you don't want an enter keypress to auto submit when a user accident hits the enter key. If so you can attach a javascript onkeypress event to each control that you want to disable this behavior for.
function disableEnterKey(e)
{
var key;
if (window.event) key = window.event.keyCode; // Internet Explorer
else key = e.which;
return (key != 13);
}
// In your aspx file Page_Load do the following foreach control you want to disable
// the enter key for:
txtYourTextBox.Attributes.Add("OnKeyPress", "return disableEnterKey(event);");
If you need to disable the Enter key submitting form completely. case use the OnKeyDown handler on <body> tag on your page.
The javascript code:
if (window.event.keyCode == 13)
{
event.returnValue = false;
event.cancel = true;
}
With JQuery this would be much cleaner, easier and the recommended method. You could make an extension with:
jQuery.fn.DisableEnterKey =
function()
{
return this.each(function()
{
$(this).keydown(function(e)
{
var key = e.charCode || e.keyCode || 0;
// return false for the enter key
return (key != 13);
})
})
};
// You can then wire it up by just adding this code for each control:
<script type="text/javascript" language="javascript">
$('#txtYourTextBox').DisableEnterKey();
</script>
If you put your content in a asp:Panel you can use the DefaultButton Property to set a different button as the default so your image button wont be clicked.
<asp:Panel runat="server" ID="pnl_Test" DefaultButton="btn_Test2">
<asp:ImageButton runat="server" ID="btn_Test1" />
<asp:Button runat="server" ID="btn_Test2" />
</asp:Panel>
In this example the btn_Test2 will be clicked when you hit enter where normally btn_Test1 would be clicked
Use Kelsey's Answer (This answer is wiki'ed)
...but please note a few things when you implement it.
I'd recommend the plain old javascript method if you're not already using jQuery. if you do that method, just return (keynum != 13) don't do something silly like if(true) return true; else return false;
You don't have to assign onkeydown from the code behind. That can be done in the markup and it's a lot cleaner when you do.
Don't disable the enter key in your entire form. You can do it in your inputs only, but if you do it in the entire form you won't be able to add a carriage return in a textarea.
If you do use jQuery, I'd recommend adding a CSS class called "disableEnterKey" and assigning it to your form elements you want to disable, then calling Kelsey's jQuery method on $(".disableEnterKey") in the document ready.
Don't answer too similar to anyone on SO, even if you don't fully agree with the answer. And even if the answer was simple and thousands of people probably have done the samething. It's "copying". Which is similar to being a "cutter" or a "tattle tale"... which is bad.
(this answer has been community wiki'ed as this question thread has gotten silly)
Use an asp:image instead. Then place some javascript code in the onclick "javascript:document.getElementById('imageClicked').setAttribute('value', 'true'); document.myform.submit();"
Set a hidden field's value (using javascript) to tell the server side code that the image was clicked.
document.getElementById('imageClicked').setAttribute('value', 'true');
Then, at the end of handling the postback on the server reset the hiddenField's value:
document.getElementById('imageClicked').setAttribute('value', 'true');
The form will execute the first button it finds on the page when you hit enter. If you can move the ImageButton further down the page so it's no longer the first button in the markup, and use CSS to position it properly, this should fix your issue. I fixed the same exact thing last week and this worked for me. I went with this solution because it didn't require JavaScript to work properly.
you want something like
<form ...>
<!-- some code here -->
<button style='display:none' onclick='return false'>here comes the magic</button>
<button>normal button </button>
</form>
See the following link.This can be solved for all default button submit problem.
http://weblog.kevinattard.com/2011/08/aspnet-disable-submit-form-on-enter-key.html
Please Use This Code
<script type="text/javascript" language="javascript">
$(document).ready(function {
$("#<%=imageClicked.ClientID%>").prop('disabled',true)
});
</script>
I've got a checkbox that's set up as below:
<asp:CheckBox ID="myCheckbox" runat="Server" OnClick="showLoadingScreen(this.checked);" AutoPostBack="true" Text="Check me for more data!" />
The function showLoadingScreen is as below:
function showLoadingScreen(isChecked) {
if (isChecked)
{
document.getElementById('form1').style.display='none';
document.getElementById('img_loading').style.display='block';
}
else { return false; }
}
I've added the else clause in hopes that I can get it to only post back when the checkbox is checked, but it's posting back in either case.
I've got a grid on the page (inside form1) that has a set of data loaded into it on page load, but in order to add some extra data to it I've added this checkbox (its a longer running process, so I only want to load it on demand, not upfront). When it's checked I want to show the loading gif, postback, grab the data, and return. If the box gets unchecked I don't want to do anything, since leaving more than enough data on the page is perfectly fine (that is to say, the data displayed upfront is a subset of the data displayed when the checkbox is checked).
Is there any way to make it so the checkbox auto posts back on checked, but not on unchecked?
Edit: Using Dark Falcon's suggestion, I've modified the checkbox to look like:
<asp:CheckBox ID="myCheckbox" runat="Server" OnClick="return showLoadingScreen(this.checked);" AutoPostBack="true" Text="Include HQ Values" />
And the javascript to be:
function showLoadingScreen(checked) {
alert(checked);
if (checked)
{
document.getElementById('form1').style.display='none';
document.getElementById('img_loading').style.display='block';
document.form1.submit(); //my own addition, to get it to post back
}
else { return false; }
}
Now, it posts back on checked, but the box is not able to be unchecked anymore. As you can see I've added an alert to show the value being passed in. It's passing in the correct value when you uncheck the box (false), but then it somehow gets checked again.
It's not a huge issue, since there's really no reason to ever uncheck the box (since as I stated before, the dataset when checked is a superset of the unchecked dataset), but I'd still like to know why it's doing that. Any ideas?
Do not set AutoPostBack in this case. "AutoPostBack" means post back to the server any time the value of this control changes... which is NOT what you want.
Instead, use GetPostBackEventReference(myCheckbox,"") to get the appropriate postback script and call this from your showLoadingScreen method if the checkbox is checked.
For your onclick handler, you need to do:
return showLoadingScreen(this.checked);
Try to avoid using _doPostback as it is a hack which you will have to know what control ID is posting back and other parameters for that Javascript function from Microsoft ASP.NET. To understand what's happening behind the scene, you have to know why there is a postback and how to prevent the postback from happening.
Here's what's happening with an ASP.NET checkbox (ASP:Checkbox) when auto-postback is set:
<ASP:Checkbox runat="server" id="chkCheckbox" AutoPostback="true" onclick="return isDoPostback(this.checked);" ClientIdMode="static" ... />
generated HTML code is:
<input type="checkbox" ... id="..." onclick="return isDoPostback(this.checked);_doPostback(...);" .../>
The custom onclick event is appended to the beginning of the onclick event of the checkbox. No matter what you do, that prepended function call will execute. Worst off, if you have a return value, the _doPostback will never get executed.
This is what you really want to do (I use a mix of jQuery and native Javascript here):
var checkbox = $("#chkCheckbox");
...
checkbox .on("change", function(e)
{ if(this.checked)
{
var isConfirmedToContinue = confirm("Continue with Postback?");
if(!isConfirmedToContinue)
{ this.checked = false; //Uncheck the checkbox since the user canceled out
var onClickDelegate = this.onclick;
if(onClickDelegate)
{ var me = this;
this.removeEventListener("click", onClickDelegate); //Remove the onclick event so that auto-postback no longer happens
setTimeout(function()
{ //Add back the onclick delegate after 250ms
me.addEventListener("click", onClickDelegate);
}, 250);
this.onclick = null; //Remove the current onclick event by nulling it out
}
}
}
});
Try using a JS routine for checking whether it is checked, and if it is set to true, try doing:
_doPostBack(checkElementReference.name, "");
_doPostBack is responsible for performing posts to the server for controls that don't normally postback. You have to pass the name of the element, which on the server happens to be the UniqueID property for the server-side checkbox control.
ASP.NET seems to be generating its own onclick event for any buttons that are generated.
Looks like this
javascript:__doPostBack(
This is preventing jQuery from working correctly.
Does anyone know how to stop asp.net engine from doing this?
Many thanks
You just need to add a return false to your jquery code that handles the button.
$("myaspbutton").click(function(e){
//your code
return false;****
});
<asp:Buttton runat="server" ID="myButton" Text="MyButton" OnClientClick="alert('hi');" />
Update:
you can bind the click event dynamically:
$('#<%=myButton.ClientID%>').click(function(e) {
//your code here
e.preventDefault();
});
Why doesn't this work?
<script src="Scripts/jquery-1.3.2.js" type="text/javascript"></script>
<script type="text/javascript">
$(document).ready(function() {
$('.myButton').click();
});
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:LinkButton id="ttt" runat="server" PostBackUrl="~/Default.aspx" CssClass="myButton">Click</asp:LinkButton>
</div>
</form>
Do you want to submit the form, or add a Click event?
Your link button translates to
<a id="ttt" class="myButton" href="javascript:WebForm_DoPos[...]">Click</a>
, so it has no on-click javascript. Therefore, .click(); does nothing.
I haven't test it, but maybe this will work:
eval($('.myButton').attr('href'));
trigger('click') fires jQuery's click event listener which .NET isn't hooked up to. You can just fire the javascript click event which will go to (or run in this case) what is in the href attribute:
$('.myButton')[0].click();
or
($('.myButton').length ? $('.myButton') : $('<a/>'))[0].click();
If your not sure that the button is going to be present on the page.
Joe
If you need the linkbutton's OnClick server-side event to fire, you need to use __doPostback(eventTarget, eventArgument).
ex:
<asp:LinkButton ID="btnMyButton" runat="Server" OnClick="Button_Click" />
<script type="text/javascript">
function onMyClientClick(){
//do some client side stuff
//'click' the link button, form will post, Button_Click will fire on back-end
//that's two underscores
__doPostBack('<%=btnMyButton.UniqueID%>', ''); //the second parameter is required and superfluous, just use blank
}
</script>
you need to assign an event handler to fire for when the click event is raised
$(document).ready(function() {
$('.myButton', '#form1')
.click(function() {
/*
Your code to run when Click event is raised.
In this case, something like window.location = "http://..."
This can be an anonymous or named function
*/
return false; // This is required as you have set a PostbackUrl
// on the LinkButton which will post the form
// to the specified URL
});
});
I have tested the above with ASP.NET 3.5 and it works as expected.
There is also the OnClientClick attribute on the Linkbutton, which specifies client side script to run when the click event is raised.
Can I ask what you are trying to achieve?
The click event handler has to actually perform an action. Try this:
$(function () {
$('.myButton').click(function () { alert('Hello!'); });
});
you need to give the linkButton a CssClass="myButton" then use this in the top
$(document).ready(function() {
$('.myButton').click(function(){
alert("hello thar");
});
});
That's a tough one. As I understand it, you want to mimic the behavior of clicking the button in javascript code. The problem is that ASP.NET adds some fancy javascript code to the onclick handler.
When manually firing an event in jQuery, only the event code added by jQuery will be executed, not the javascript in the onclick attribute or the href attribute. So the idea is to create a new event handler that will execute the original javascript defined in attributes.
What I'm going to propose hasn't been tested, but I'll give it a shot:
$(document).ready(function() {
// redefine the event
$(".myButton").click(function() {
var href = $(this).attr("href");
if (href.substr(0,10) == "javascript:") {
new Function(href.substr(10)).call(this);
// this will make sure that "this" is
// correctly set when evaluating the javascript
// code
} else {
window.location = href;
}
return false;
});
// this will fire the click:
$(".myButton").click();
});
Just to clarify, only FireFox suffers from this issue. See http://www.devtoolshed.com/content/fix-firefox-click-event-issue. In FireFox, anchor (a) tags have no click() function to allow JavaScript code to directly simulate click events on them. They do allow you to map the click event of the anchor tag, just not to simulate it with the click() function.
Fortunately, ASP.NET puts the JavaScript postback code into the href attribute, where you can get it and run eval on it. (Or just call window.location.href = document.GetElementById('LinkButton1').href;).
Alternatively, you could just call __doPostBack('LinkButton1'); note that 'LinkButton1' should be replaced by the ClientID/UniqueID of the LinkButton to handle naming containers, e.g. UserControls, MasterPages, etc.
Jordan Rieger