I have javascript custom click event which I want to return false the click event running. The following is my code but seems not success. It will check if the comment is empty, then not jumping back to previous windows. If the comment is not empty, then the FeedbackModal will be shown.
$(document).on('click.feed', '#back', function(){
event.preventDefault();
$('#FeedbackModal').toggle();
str = $('input[name="comment"]').val();
str = str.trim();
if (str == "") {
alert("comment cannot be empty");
return false;
});
This is the html of the button.
<button type="button" id="backtopreviouswindows" data-dismiss="modal">Back</button>
I'm trying to stop the submit if an error exists and go through the submission if no error exist.
This is just a section of the code. Regex works correctly, also the error texts were showing up too. The thing is that now I'm trying to control the submit proccess and due to an error (console is not showing up anything) the error text is not showing up and the submission is just going through even if an input error exists.
There is a mistake that I cannot figure out (No jquery please)
var sub = document.querySelector("#register input[type='submit']");//the submit botton
var err_text_1 = "First name must be filled out!";
sub.onsubmit = function(){
if (first_name == null || first_name == "") {
err_holder_1.innerHTML = err_text_1;
return false;
}
else {
err_holder_1.style.display = "none";
}
}
To prevent submit add event in the function and return false like so:
sub.onsubmit = function (event) {
// Will prevent submit
event.preventDefault();
return false;
};
Also select the form you are submitting not the button itself. So:
var sub = document.getElementById('ActionForm');
Hope this helps.
You need to select the form like
var sub = document.querySelector("#register");//If register is your form id Not input[type='submit']
<script>
function no_email_confirm() {
if (document.getElementsByName("no_email")[0].checked == false) {
return true;
} else {
var box= confirm("Sure?");
if (box==true)
return true;
else
document.getElementsByName("no_email")[0].checked == false;
}
}
</script>
And here is my HTML for the checkbox:
<input type="checkbox" id="no_email" name="no_email" onchange="no_email_confirm()"></input>
For some reason, this gives me the confirm pop up the first time I check the box, but not for any click after that. Also, even if I click "Cancel" it still checks the check box. I've searched on here and for some reason, no matter what I try, I can't get it to work properly.
It should confirm if they really want to check the box, if they select "Yes" then it checks it, if not, then it doesn't check it. I can get it to work without the name no_email, but I can't change that..
Anyone have any ideas?
Looks like you've got several errors in there, most notably using == when you probably meant =. Instead, add an event listener and make sure the assignment works:
var box = document.querySelector('#no_email');
box.addEventListener('change', function no_email_confirm() {
if (this.checked == false) {
return true;
} else {
var confirmation= confirm("This means that the VENDOR will NOT RECEIVE ANY communication!!!!");
if (confirmation)
return true;
else
box.checked = false;
}
});
http://jsfiddle.net/A3VGg/1/
I have this section of code:
function createDownload() {
var category, format, specification, download;
$('#submitform').click(function() {
category = $('#cate').val();
format = $('#form').val();
specification = $('#spec').val();
if (category == "NULL" || format == "NULL" || specification == "NULL") {
alert("Please select all options.");
return false;
} else {
download = "pdfs/"+specification+format+category+".pdf";
window.open(download);
}
});
}
Now... In Internet Explorer it says there is an "Error on the page" - Message: 'return' statement outside of function and I have to click the button again.
In Firefox, Chrome and Safari - I have to click the button twice to get the PDF to appear... (and no errors)...
Now why could that be?!
As per request - My Form declaration:
<form method="post" action="javascript: return false;" onSubmit="createDownload();">
<form method="post" action="javascript: return false;" onSubmit="createDownload();">
Since you are using return false not in a function it is throwing the error. You will have to put that in an anynymous function.
Something like
<form method="post" action="javascript: function() {return false;}" onSubmit="createDownload();">
will work
Better to bind the event .submit() for the form
<form method="post" id="frm1"></form>
$("#frm1").submit(function(){
// your code
return false;
});
You need to change your action='javascript: return false;' and remove the onsubmit. It should become action='javascript: createDownload();'
Try removing the return. It seems you don't even need it, and if that's really the cause of the problem then what's the point keeping it there?
First, you need to remove the action from the form - it serves no purpose here. Also, assuming #submitForm refers to the form submit button, your first click will attach the click handler and the second click will actually call it. Instead, remove the onsubmit attribute and just attach the handler in the usual way to either the button click or form submit event, being sure to cancel the event in either case:
jQuery(function($) {
$('#submitform').click(function() {
// or: $('#formID').submit(function() {
var category, format, specification, download;
category = $('#cate').val();
format = $('#form').val();
specification = $('#spec').val();
if (category == "NULL" || format == "NULL" || specification == "NULL") {
alert("Please select all options.");
} else {
download = "pdfs/"+specification+format+category+".pdf";
window.open(download);
}
return false;
});
});
I'd like to track changes in inputs in a form via javascript. My intent is (but not limited) to
enable "save" button only when something has changed
alert if the user wants to close the page and something is not saved
Ideas?
Loop through all the input elements, and put an onchange handler on each. When that fires, set a flag which lets you know the form has changed. A basic version of that would be very easy to set up, but wouldn't be smart enough to recognize if someone changed an input from "a" to "b" and then back to "a". If it were important to catch that case, then it'd still be possible, but would take a bit more work.
Here's a basic example in jQuery:
$("#myForm")
.on("input", function() {
// do whatever you need to do when something's changed.
// perhaps set up an onExit function on the window
$('#saveButton').show();
})
;
Text form elements in JS expose a .value property and a .defaultValue property, so you can easily implement something like:
function formChanged(form) {
for (var i = 0; i < form.elements.length; i++) {
if(form.elements[i].value != form.elements[i].defaultValue) return(true);
}
return(false);
}
For checkboxes and radio buttons see whether element.checked != element.defaultChecked, and for HTML <select /> elements you'll need to loop over the select.options array and check for each option whether selected == defaultSelected.
You might want to look at using a framework like jQuery to attach handlers to the onchange event of each individual form element. These handlers can call your formChanged() code and modify the enabled property of your "save" button, and/or attach/detach an event handler for the document body's beforeunload event.
Here's a javascript & jquery method for detecting form changes that is simple. It disables the submit button until changes are made. It detects attempts to leave the page by means other than submitting the form. It accounts for "undos" by the user, it is encapsulated within a function for ease of application, and it doesn't misfire on submit. Just call the function and pass the ID of your form.
This function serializes the form once when the page is loaded, and again before the user leaves the page. If the two form states are different, the prompt is shown.
Try it out: http://jsfiddle.net/skibulk/ev5rE/
function formUnloadPrompt(formSelector) {
var formA = $(formSelector).serialize(), formB, formSubmit = false;
// Detect Form Submit
$(formSelector).submit( function(){
formSubmit = true;
});
// Handle Form Unload
window.onbeforeunload = function(){
if (formSubmit) return;
formB = $(formSelector).serialize();
if (formA != formB) return "Your changes have not been saved.";
};
// Enable & Disable Submit Button
var formToggleSubmit = function(){
formB = $(formSelector).serialize();
$(formSelector+' [type="submit"]').attr( "disabled", formA == formB);
};
formToggleSubmit();
$(formSelector).change(formToggleSubmit);
$(formSelector).keyup(formToggleSubmit);
}
// Call function on DOM Ready:
$(function(){
formUnloadPrompt('form');
});
Try
function isModifiedForm(form){
var __clone = $(form).clone();
__clone[0].reset();
return $(form).serialize() == $(__clone).serialize();
}
Hope its helps ))
If your using a web app framework (rails, ASP.NET, Cake, symfony), there should be packages for ajax validation,
http://webtecker.com/2008/03/17/list-of-ajax-form-validators/
and some wrapper on onbeforeunload() to warn users taht are about to close the form:
http://pragmatig.wordpress.com/2008/03/03/protecting-userdata-from-beeing-lost-with-jquery/
Detecting Unsaved Changes
I answered a question like this on Ars Technica, but the question was framed such that the changes needed to be detected even if the user does not blur a text field (in which case the change event never fires). I came up with a comprehensive script which:
enables submit and reset buttons if field values change
disables submit and reset buttons if the form is reset
interrupts leaving the page if form data has changed and not been submitted
supports IE 6+, Firefox 2+, Safari 3+ (and presumably Opera but I did not test)
This script depends on Prototype but could be easily adapted to another library or to stand alone.
$(document).observe('dom:loaded', function(e) {
var browser = {
trident: !!document.all && !window.opera,
webkit: (!(!!document.all && !window.opera) && !document.doctype) ||
(!!window.devicePixelRatio && !!window.getMatchedCSSRules)
};
// Select form elements that won't bubble up delegated events (eg. onchange)
var inputs = $('form_id').select('select, input[type="radio"], input[type="checkbox"]');
$('form_id').observe('submit', function(e) {
// Don't bother submitting if form not modified
if(!$('form_id').hasClassName('modified')) {
e.stop();
return false;
}
$('form_id').addClassName('saving');
});
var change = function(e) {
// Paste event fires before content has been pasted
if(e && e.type && e.type == 'paste') {
arguments.callee.defer();
return false;
}
// Check if event actually results in changed data
if(!e || e.type != 'change') {
var modified = false;
$('form_id').getElements().each(function(element) {
if(element.tagName.match(/^textarea$/i)) {
if($F(element) != element.defaultValue) {
modified = true;
}
return;
} else if(element.tagName.match(/^input$/i)) {
if(element.type.match(/^(text|hidden)$/i) && $F(element) != element.defaultValue) {
modified = true;
} else if(element.type.match(/^(checkbox|radio)$/i) && element.checked != element.defaultChecked) {
modified = true;
}
}
});
if(!modified) {
return false;
}
}
// Mark form as modified
$('form_id').addClassName('modified');
// Enable submit/reset buttons
$('reset_button_id').removeAttribute('disabled');
$('submit_button_id').removeAttribute('disabled');
// Remove event handlers as they're no longer needed
if(browser.trident) {
$('form_id').stopObserving('keyup', change);
$('form_id').stopObserving('paste', change);
} else {
$('form_id').stopObserving('input', change);
}
if(browser.webkit) {
$$('#form_id textarea').invoke('stopObserving', 'keyup', change);
$$('#form_id textarea').invoke('stopObserving', 'paste', change);
}
inputs.invoke('stopObserving', 'change', arguments.callee);
};
$('form_id').observe('reset', function(e) {
// Unset form modified, restart modified check...
$('reset_button_id').writeAttribute('disabled', true);
$('submit_button_id').writeAttribute('disabled', true);
$('form_id').removeClassName('modified');
startObservers();
});
var startObservers = (function(e) {
if(browser.trident) {
$('form_id').observe('keyup', change);
$('form_id').observe('paste', change);
} else {
$('form_id').observe('input', change);
}
// Webkit apparently doesn't fire oninput in textareas
if(browser.webkit) {
$$('#form_id textarea').invoke('observe', 'keyup', change);
$$('#form_id textarea').invoke('observe', 'paste', change);
}
inputs.invoke('observe', 'change', change);
return arguments.callee;
})();
window.onbeforeunload = function(e) {
if($('form_id').hasClassName('modified') && !$('form_id').hasClassName('saving')) {
return 'You have unsaved content, would you really like to leave the page? All your changes will be lost.';
}
};
});
I would store each fields value in a variable when the page loads, then compare those values when the user unloads the page. If any differences are detected you will know what to save and better yet, be able to specifically tell the user what data will not be saved if they exit.
// this example uses the prototype library
// also, it's not very efficient, I just threw it together
var valuesAtLoad = [];
var valuesOnCheck = [];
var isDirty = false;
var names = [];
Event.observe(window, 'load', function() {
$$('.field').each(function(i) {
valuesAtLoad.push($F(i));
});
});
var checkValues = function() {
var changes = [];
valuesOnCheck = [];
$$('.field').each(function(i) {
valuesOnCheck.push($F(i));
});
for(var i = 0; i <= valuesOnCheck.length - 1; i++ ) {
var source = valuesOnCheck[i];
var compare = valuesAtLoad[i];
if( source !== compare ) {
changes.push($$('.field')[i]);
}
}
return changes.length > 0 ? changes : [];
};
setInterval(function() { names = checkValues().pluck('id'); isDirty = names.length > 0; }, 100);
// notify the user when they exit
Event.observe(window, 'beforeunload', function(e) {
e.returnValue = isDirty ? "you have changed the following fields: \r\n" + names + "\r\n these changes will be lost if you exit. Are you sure you want to continue?" : true;
});
I've used dirtyforms.js. Works well for me.
http://mal.co.nz/code/jquery-dirty-forms/
To alert the user before closing, use unbeforeunload:
window.onbeforeunload = function() {
return "You are about to lose your form data.";
};
I did some Cross Browser Testing.
On Chrome and Safari this is nice:
<form onchange="validate()">
...
</form>
For Firefox + Chrome/Safari I go with this:
<form onkeydown="validate()">
...
<input type="checkbox" onchange="validate()">
</form>
Items like checkboxes or radiobuttons need an own onchange event listener.
Attach an event handler to each form input/select/textarea's onchange event. Setting a variable to tell you if you should enable the "save" button. Create an onunload hander that checks for a dirty form too, and when the form is submitted reset the variable:
window.onunload = checkUnsavedPage;
var isDirty = false;
var formElements = //Get a reference to all form elements
for(var i = 0; len = formElements.length; i++) {
//Add onchange event to each element to call formChanged()
}
function formChanged(event) {
isDirty = false;
document.getElementById("savebtn").disabled = "";
}
function checkUnsavedPage() {
if (isDirty) {
var isSure = confirm("you sure?");
if (!isSure) {
event.preventDefault();
}
}
}
Here's a full implementation of Dylan Beattie's suggestion:
Client/JS Framework for "Unsaved Data" Protection?
You shouldn't need to store initial values to determine if the form has changed, unless you're populating it dynamically on the client side (although, even then, you could still set up the default properties on the form elements).
You can also check out this jQuery plugin I built at jQuery track changes in forms plugin
See the demo here and download the JS here
If you are open to using jQuery, see my answer a similar question:
Disable submit button unless original form data has changed.
I had the same challenge and i was thinking of a common solution. The code below is not perfect, its from initial r&d. Following are the steps I used:
1) Move the following JS to a another file (say changeFramework.js)
2) Include it in your project by importing it
3) In your html page, whichever control needs monitoring, add the class "monitorChange"
4) The global variable 'hasChanged' will tell, if there is any change in the page you working on.
<script type="text/javascript" id="MonitorChangeFramework">
// MONITOR CHANGE FRAMEWORK
// ALL ELEMENTS WITH CLASS ".monitorChange" WILL BE REGISTERED FOR CHANGE
// ON CHANGE IT WILL RAISE A FLAG
var hasChanged;
function MonitorChange() {
hasChanged = false;
$(".monitorChange").change(function () {
hasChanged = true;
});
}
Following are the controls where I used this framework:
<textarea class="monitorChange" rows="5" cols="10" id="testArea"></textarea></br>
<div id="divDrinks">
<input type="checkbox" class="chb monitorChange" value="Tea" />Tea </br>
<input type="checkbox" class="chb monitorChange" value="Milk" checked='checked' />Milk</br>
<input type="checkbox" class="chb monitorChange" value="Coffee" />Coffee </br>
</div>
<select id="comboCar" class="monitorChange">
<option value="volvo">Volvo</option>
<option value="saab">Saab</option>
<option value="mercedes">Mercedes</option>
<option value="audi">Audi</option>
</select>
<button id="testButton">
test</button><a onclick="NavigateTo()">next >>> </a>
I believe there can be huge improvement in this framework. Comment/Changes/feedbacks are welcome. :)