preventDefault on submitting form - javascript

I would like run function on my form submit (validate with Foundation framework) :
$($newsletter).on('formvalid.zf.abide', function(ev) {
ev.preventDefault();
alert('validate!');
openRevealNewsletter(this.getAttribute('action'));
});
I've my alert when my form is valid, but my preventDefault() don't work. My form is submitted :(

first of all easy way to make this work done is use
<button type="button">submit</button>
instead of
<button type="submit">submit</button>
to submit the form programmatically in java script use
document.getElementById("FormID").submit();
this will submit your form when you call this script also prevent default will not required once you replace submit with button in submit button

Intercept submit with submit event.
$($newsletter).on("submit",function(e) {
e.preventDefault();
console.log("submit intercepted");
return false;
});
$($newsletter).on("forminvalid.zf.abide", function(e,target) {
console.log("form is invalid");
//show error messages
});
$($newsletter).on("formvalid.zf.abide", function(e,target) {
console.log("form is valid");
//process form
openRevealNewsletter(this.getAttribute('action'));
});

Please try this:
$($newsletter).on('formvalid.zf.abide', function(ev) {
alert('validate!');
openRevealNewsletter(this.getAttribute('action'));
return false;
});
This will stop the form post on a false returned value.
When you are using return false,automatically it is doing 3 separate things when you call it:
1.event.preventDefault();
2.event.stopPropagation();
3.Stops callback execution and it returns immediately when callback are called.

Related

Javascript return false; is not cancelling a form submit for another .submit jQuery call

I have this jQuery function injected on every page in order to disable submit buttons after they are clicked.
$('form').submit(function () {
var btn = $('input[type=submit]', this);
disableButtonOrLink.disableSubmit(btn);
btn = $('button[type=submit]', this);
disableButtonOrLink.disableSubmit(btn);
});
The problem is that I also have some backend validation that is sometimes attached to the form in the the shape of something like this
<form action="someAction" method="post" name="someForm" class="form"
onsubmit="var invalid=false;
invalid=someAction();
if(invalid){return false;}"
id="someForm">
The issue I am having that is occurs is that the ('form').submit action is always being called after the return false. The form isn't actually being submitted due to the return false; however this jQuery function is still being called after. Is there anyway to prevent this .submit from being called?
Just to clarify exactly what is happening:
The onSubmit on the form is being called;
The return false section is being hit and properly canceling the submit;
The ('form').submit is still being called after the onSubmit completes as if the form's submit wasn't canceled and is disabling buttons.
I would like to prevent the last step from occurring.
You can use JQuery to find those buttons inside form and use a method from preventing stuff that they normally do.
Example:
$("form button").on('click', function(e){
e.preventDefault();
});
I would probably try something like this
$('#someForm').on('submit', function(e) {
if ($(this).data('some-action')) {
e.preventDefault();
return false;
}
//... then disable buttons, etc
});
In this case you need to add the attribute data-some-action to the form, evaluated with whatever backend validation you are doing.
UPDATE
$('#someForm').on('submit', function(e) {
if ($(this).data('some-action') == 'error-message') {
e.preventDefault();
alert('error!');
return false;
}
if ($(this).data('some-action') == 'reload') {
e.preventDefault();
document.location.reload(true);
}
//... then disable buttons, etc
});

How do I make HTML5 show validation errors without making user click a submit button? [duplicate]

I have this form in my app and I will submit it via AJAX, but I want to use HTML for client-side validation. So I want to be able to force the form validation, perhaps via jQuery.
I want to trigger the validation without submitting the form. Is it possible?
To check whether a certain field is valid, use:
$('#myField')[0].checkValidity(); // returns true|false
To check if the form is valid, use:
$('#myForm')[0].checkValidity(); // returns true|false
Show html5 built-in error
if (! $('#myForm')[0].checkValidity()) {
$('#myForm')[0].reportValidity()
}
Keep in mind that, HTML5 validation is not supported in all browsers till now.
below code works for me,
$("#btn").click(function () {
if ($("#frm")[0].checkValidity())
alert('sucess');
else
//Validate Form
$("#frm")[0].reportValidity()
});
I found this solution to work for me.
Just call a javascript function like this:
action="javascript:myFunction();"
Then you have the html5 validation... really simple :-)
if $("form")[0].checkValidity()
$.ajax(
url: "url"
type: "post"
data: {
}
dataType: "json"
success: (data) ->
)
else
#important
$("form")[0].reportValidity()
from: html5 form validation
Here is a more general way that is a bit cleaner:
Create your form like this (can be a dummy form that does nothing):
<form class="validateDontSubmit">
...
Bind all forms that you dont really want to submit:
$(document).on('submit','.validateDontSubmit',function (e) {
//prevent the form from doing a submit
e.preventDefault();
return false;
})
Now lets say you have an <a> (within the <form>) that on click you want to validate the form:
$('#myLink').click(function(e){
//Leverage the HTML5 validation w/ ajax. Have to submit to get em. Wont actually submit cuz form
//has .validateDontSubmit class
var $theForm = $(this).closest('form');
//Some browsers don't implement checkValidity
if (( typeof($theForm[0].checkValidity) == "function" ) && !$theForm[0].checkValidity()) {
return;
}
//if you've gotten here - play on playa'
});
Few notes here:
I have noticed that you don't have to actually submit the form for validation to occur - the call to checkValidity() is enough (at least in chrome). If others could add comments with testing this theory on other browsers I'll update this answer.
The thing that triggers the validation does not have to be within the <form>. This was just a clean and flexible way to have a general purpose solution..
2022 vanilla JS solution
Pure JavaScript has all the functions you need for this. I know the question was about jQuery, but even the answers with jQuery use these functions, which are checkValidity() and reportValidity().
Test entire form
let form = document.getElementById('formId');
// Eventlistener can be another event and on another DOM object this is just an example
form.addEventListener('submit', function (event) {
// Only needed if event is submit, otherwise this line can be skipped
event.preventDefault();
// This is the important part, test if form is valid
if (form.checkValidity() === false){
// This is the magic function that displays the validation errors to the user
form.reportValidity();
return;
}
// Code if all fields are valid; continue form submit or make Ajax call.
})
Test specific field
checkValidity() and reportValidity() can not only be used on the form, but also on specific fields. No need to create a form or a dummy submit button if not needed.
// Get field of interest
let inputElement = document.querySelector("[name='" + inputName + "']");
// Check if the element is valid
if (inputElement.checkValidity() === false){
// If not, show the errors to the user
inputElement.reportValidity();
return;
}
// Nothing? Great, continue to the Ajax call or whatever
This has to be in a function called by an event listener to make sense, obviously.
May be late to the party but yet somehow I found this question while trying to solve similar problem. As no code from this page worked for me, meanwhile I came up with solution that works as specified.
Problem is when your <form> DOM contain single <button> element, once fired, that <button> will automatically sumbit form. If you play with AJAX, You probably need to prevent default action. But there is a catch: If you just do so, You will also prevent basic HTML5 validation. Therefore, it is good call to prevent defaults on that button only if the form is valid. Otherwise, HTML5 validation will protect You from submitting. jQuery checkValidity() will help with this:
jQuery:
$(document).ready(function() {
$('#buttonID').on('click', function(event) {
var isvalidate = $("#formID")[0].checkValidity();
if (isvalidate) {
event.preventDefault();
// HERE YOU CAN PUT YOUR AJAX CALL
}
});
});
Code described above will allow You to use basic HTML5 validation (with type and pattern matching) WITHOUT submitting form.
You speak of two different things "HTML5 validation" and validation of HTML form using javascript/jquery.
HTML5 "has" built-in options for validating a form. Such as using "required" attribute on a field, which could (based on browser implementation) fail form submission without using javascript/jquery.
With javascrip/jquery you can do something like this
$('your_form_id').bind('submit', function() {
// validate your form here
return (valid) ? true : false;
});
var $myForm = $('#myForm ');
if (!$myForm[0].checkValidity()) {
$('<input type="submit">').hide().appendTo($myForm).click().remove();
}
To check all the required fields of form without using submit button you can use below function.
You have to assign required attribute to the controls.
$("#btnSave").click(function () {
$(":input[required]").each(function () {
var myForm = $('#form1');
if (!$myForm[0].checkValidity())
{
$(myForm).submit();
}
});
});
You don't need jQuery to achieve this. In your form add:
onsubmit="return buttonSubmit(this)
or in JavaScript:
myform.setAttribute("onsubmit", "return buttonSubmit(this)");
In your buttonSubmit function (or whatver you call it), you can submit the form using AJAX. buttonSubmit will only get called if your form is validated in HTML5.
In case this helps anyone, here is my buttonSubmit function:
function buttonSubmit(e)
{
var ajax;
var formData = new FormData();
for (i = 0; i < e.elements.length; i++)
{
if (e.elements[i].type == "submit")
{
if (submitvalue == e.elements[i].value)
{
submit = e.elements[i];
submit.disabled = true;
}
}
else if (e.elements[i].type == "radio")
{
if (e.elements[i].checked)
formData.append(e.elements[i].name, e.elements[i].value);
}
else
formData.append(e.elements[i].name, e.elements[i].value);
}
formData.append("javascript", "javascript");
var action = e.action;
status = action.split('/').reverse()[0] + "-status";
ajax = new XMLHttpRequest();
ajax.addEventListener("load", manageLoad, false);
ajax.addEventListener("error", manageError, false);
ajax.open("POST", action);
ajax.send(formData);
return false;
}
Some of my forms contain multiple submit buttons, hence this line if (submitvalue == e.elements[i].value). I set the value of submitvalue using a click event.
This way works well for me:
Add onSubmit attribute in your form, don't forget to include return in the value.
<form id='frm-contact' method='POST' action='' onSubmit="return contact()">
Define the function.
function contact(params) {
$.ajax({
url: 'sendmail.php',
type: "POST",
dataType: "json",
timeout: 5000,
data: { params:params },
success: function (data, textStatus, jqXHR) {
// callback
},
error: function(jqXHR, textStatus, errorThrown) {
console.log(jqXHR.responseText);
}
});
return false;
}
I had a rather complex situation, where I needed multiple submit buttons to process different things. For example, Save and Delete.
The basis was that it was also unobtrusive, so I couldn't just make it a normal button. But also wanted to utilize html5 validation.
As well the submit event was overridden in case the user pressed enter to trigger the expected default submission; in this example save.
Here is the efforts of the processing of the form to still work with/without javascript and with html5 validation, with both submit and click events.
jsFiddle Demo - HTML5 validation with submit and click overrides
xHTML
<form>
<input type="text" required="required" value="" placeholder="test" />
<button type="submit" name="save">Save</button>
<button type="submit" name="delete">Delete</button>
</form>
JavaScript
//wrap our script in an annonymous function so that it can not be affected by other scripts and does not interact with other scripts
//ensures jQuery is the only thing declared as $
(function($){
var isValid = null;
var form = $('form');
var submitButton = form.find('button[type="submit"]')
var saveButton = submitButton.filter('[name="save"]');
var deleteButton = submitButton.filter('[name="delete"]');
//submit form behavior
var submitForm = function(e){
console.log('form submit');
//prevent form from submitting valid or invalid
e.preventDefault();
//user clicked and the form was not valid
if(isValid === false){
isValid = null;
return false;
}
//user pressed enter, process as if they clicked save instead
saveButton.trigger('click');
};
//override submit button behavior
var submitClick = function(e){
//Test form validitiy (HTML5) and store it in a global variable so both functions can use it
isValid = form[0].checkValidity();
if(false === isValid){
//allow the browser's default submit event behavior
return true;
}
//prevent default behavior
e.preventDefault();
//additional processing - $.ajax() etc
//.........
alert('Success');
};
//override submit form event
form.submit(submitForm);
//override submit button click event
submitButton.click(submitClick);
})(jQuery);
The caveat to using Javascript is that the browser's default onclick must propagate to the submit event MUST occur in order to display the error messages without supporting each browser in your code.
Otherwise if the click event is overridden with event.preventDefault() or return false it will never propagate to the browser's submit event.
The thing to point out is that in some browsers will not trigger the form submit when the user presses enter, instead it will trigger the first submit button in the form. Hence there is a console.log('form submit') to show that it does not trigger.
You can do it without submitting the form.
For example, if the form submit button with id "search" is in the other form . You can call click event on that submit button and call ev.preventDefault after that.
For my case I validate form B from Form A submission.
Like this
function validateFormB(ev){ // DOM Event object
//search is in Form A
$("#search").click();
ev.preventDefault();
//Form B validation from here on
}
$(document).on("submit", false);
submitButton.click(function(e) {
if (form.checkValidity()) {
form.submit();
}
});
$("#form").submit(function() { $("#saveButton").attr("disabled", true); });
not a best answer but works for me.
I know this has already been answered, but I have another possible solution.
If using jquery, you can do this.
First create a couple of extensions on jquery so you can resuse these as needed.
$.extend({
bypassDefaultSubmit: function (formName, newSubmitMethod) {
$('#'+formName).submit(function (event) {
newSubmitMethod();
event.preventDefault();
}
}
});
Next do something like this where you want to use it.
<script type="text/javascript">
/*if you want to validate the form on a submit call,
and you never want the form to be submitted via
a normal submit operation, or maybe you want handle it.
*/
$(function () {
$.bypassDefaultSubmit('form1', submit);
});
function submit(){
//do something, or nothing if you just want the validation
}
</script>
This worked form me to display the native HTML 5 error messages with form validation.
<button id="btnRegister" class="btn btn-success btn btn-lg" type="submit"> Register </button>
$('#RegForm').on('submit', function ()
{
if (this.checkValidity() == false)
{
// if form is not valid show native error messages
return false;
}
else
{
// if form is valid , show please wait message and disable the button
$("#btnRegister").html("<i class='fa fa-spinner fa-spin'></i> Please Wait...");
$(this).find(':submit').attr('disabled', 'disabled');
}
});
Note: RegForm is the form id.
Reference
Hope helps someone.
This is a pretty straight forward way of having HTML5 perform validation for any form, while still having modern JS control over the form. The only caveat is the submit button must be inside the <form>.
html
<form id="newUserForm" name="create">
Email<input type="email" name="username" id="username" size="25" required>
Phone<input type="tel" id="phone" name="phone" pattern="(?:\(\d{3}\)|\d{3})[- ]?\d{3}[- ]?\d{4}" size="12" maxlength="12" required>
<input id="submit" type="submit" value="Create Account" >
</form>
js
// bind in ready() function
jQuery( "#submit" ).click( newAcctSubmit );
function newAcctSubmit()
{
var myForm = jQuery( "#newUserForm" );
// html 5 is doing the form validation for us,
// so no need here (but backend will need to still for security)
if ( ! myForm[0].checkValidity() )
{
// bonk! failed to validate, so return true which lets the
// browser show native validation messages to the user
return true;
}
// post form with jQuery or whatever you want to do with a valid form!
var formVars = myForm.serialize();
etc...
}
I think the best approach
will be using jQuery Validation plugin which uses best practice for form validation and it also has good browser support. So you don't need to worry about browser compatibility issues.
And we can use jQuery validation valid() function which checks whether the selected form is valid or whether all selected elements are valid without submitting the form.
<form id="myform">
<input type="text" name="name" required>
<br>
<button type="button">Validate!</button>
</form>
<script>
var form = $( "#myform" );
form.validate();
$( "button" ).click(function() {
console.log( "Valid: " + form.valid() );
});
</script>
According to the question html5 validity should be validate able using jQuery at first and in most of the answer this is not happening and the reason for this is as following:
while validating using html5 form's default function
checkValidity();// returns true/false
we need to understand that jQuery returns object array, while selecting like this
$("#myForm")
therefore, you need to specify the first index to make checkValidity() function work
$('#myForm')[0].checkValidity()
here is the complete solution:
<button type="button" name="button" onclick="saveData()">Save</button>
function saveData()
{
if($('#myForm')[0].checkValidity()){
$.ajax({
type: "POST",
url: "save.php",
data: data,
success: function(resp){console.log("Response: "+resp);}
});
}
}

How to intercept a submit button click?

I have a form and a submit button.
I want to do a quick check on some of the fields (if one isn't filled in, then to blank some of the others).
I would rather not change the HTML for the button, I would like to just to do this in jQuery and not add any "onclick" attributes to the button.
HTML:
<input class="cssButton button_in_cart" type="submit" value="Add to Bag" style="width: 80px;">
jQuery (attempted):
$("input.button_in_cart").mousedown(function () {
alert("clicked");
});
This doesn't work, it still submits the form without showing the alert. Thanks.
Do not use any form of click event for form processing as keyboard submission will bypass your code!
Use the submit event handler instead and return false (or e.preventDefault()) to stop the submit proceeding.
e.g.
$('#myform').submit(function(e){
// Do your validation here
// ...
// Then conditionally stop the submit from firing
if (someValidateFails){
e.preventDefault()
}
});
You can use the return value of the function to prevent the form submission
<form name="myForm" onsubmit="return validateMyForm();">
and function like
<script type="text/javascript">
function validateMyForm()
{
if(check if your conditions are not satisfying)
{
alert("validation failed false");
returnToPreviousPage();
return false;
}
alert("validations passed");
return true;
}
</script>
In case of Chrome 27.0.1453.116 m if above code does not work, please set the event handler's parameter's returnValue field to false to get it to work.
make type as 'button' first
<input class="cssButton button_in_cart" type="submit" value="Add to Bag" style="width: 80px;">
$("input.button_in_cart").mousedown(function (e) {
e.preventDefault();
alert("clicked");
// do the form submit
document.forms[0].submit();
});
There are two main ways to "stop" an event.
The first one is to return false; and the other one is to e.preventDefault();.
Teh difference in these two ways is that using e.preventDefault(); will stop the entire event from proceeding and won't propagate the DOM.
I would use the following:
$("input.button_in_cart").mousedown(function () {
alert("clicked");
return false;
})

Catch submit event, validate and if o.k. continue to submit the form

It seems like something what supposedly looks very easy to implement is not possible.
I want to catch the submit event from a form and do some validation first. If the validation is done, I want to continue to submit the form.
$('#myform').submit(function(e){
e.preventDefault();
var valid = true;
//- do some validation magic
if(valid){
$(this).submit();
// $('#myform').submit(); // does not work as well
}else{
//- give feedback
$('#error').fadeIn();
}
})
That last part seems to be the issue; while triggering the submit event on the form when valid brings the script in an infinite loop.
Off course I can wrap everything in an AJAX call, but I prefer to just 'plain-simple' submit the form.
So only prevent the submission when it fails, there is no need to resubmit.
$('#myform').submit( function (e) {
var valid = true;
//- do some validation magic
if (!valid) {
$('#error').fadeIn();
e.preventDefault();
}
});

How to submit AJAX forms with user clicking enter?

I am submitting a form with AJAX:
$("#frmConferenceSettings").on("submit",function(event){
// disable default click operation
event.preventDefault();
// run the AJAX submit
update_conference_settings();
});
This works fine, however the effect is such that only the submit button will work to submit the form; hitting enter whilst in a form input is disabled by event.preventDefault().
If event.preventDefault() is removed the form submits when the user is in an input field and hits enter, but the AJAX via update_conference_settings() is lost.
How can I allow the form to be submitted by hitting enter, whilst preserving the AJAX?
You could only call event.preventDefault() if it's a certain type (i.e. click) event.
You can try to bind a keypress event and trigger() the handler on your button.
Didn't try it but it should work.
UPDATE replace bind with on
$(document).on('keypress', function(e){
if(e.which === 13) { // enter
$('#button_id').trigger('click');
}
});
You could remove the event.preventDefault() and put 'return false' after update_conference_settings().
Edit: this is how this should work:
$(function(){
$("#my-form").submit(function(){
update_conference_settings(function(){
//Here you can redirect to new page or do nothing
//window.location.href = "/submit-page"
console.log("3) update_conference_settings complete");
});
console.log("2) Default form submit cancelled");
return false;
});
function update_conference_settings(callback)
{
//Simulate ajax latency
console.log("1) Init ajax call");
setTimeout(function(){
callback();
}, 250);
}
});
See this in action here:
http://jsfiddle.net/6mNhX/6/

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