I was trying to prevent multiple submit. To prevent to submit the same value, I called window.alert to stop the process and tell the user the input value is already registered. The problem is the submit seems to be clickable after the alert window opened. Because after clicking the button several times after the alert window opens, and I closed the alert window. the alert window immediately re-opened without any clicks. the submit button seems to clickable after the windo open. how to disable all input right after the alert window open?
I was trying to disable a button by setting the state. However, it didn't work.
HTML
<form onSubmit={(e) => submitHandler(e)}>
<input
name="words"
value={words}
placeholder="Enter Tag for search"
onChange={(e) => onChangeHandler(e)}
/>
{disable ? (
<h1>updating</h1>
) : (
<button type="submit" disable={disable}>
submit
</button>
)}
</form>
const submitHandler = (e) => {
e.preventDefault();
if (!words) {
return null;
}
setNewSearchWordsState({ ...newSearchWordsState, disable: true });
const newList = list.map((item, idx) => {
if (idx === id) {
item.searchWords.map((searchWord) => {
if (searchWord === words) {
setNewSearchWordsState({ ...newSearchWordsState, words: '' });
window.alert(`${words} already registered`);
}
item.searchWords.push(words.toLowerCase());
});
}
return {
...item,
};
});
updateSearchWords(newList);
setNewSearchWordsState({ words: '', disable: false });
};
You may want try this working sample https://codepen.io/cunlay/pen/BaaROPG
// HTML
<form onsubmit="submitHandler()">
<input id="words" onkeyup="changeHandler()" placeholder="Enter Tag for search" />
<button type="submit" id="btn" disabled=true>Submit</button>
</form>
//JAVASCRIPT
<script>
function changeHandler(){
var words = document.getElementById('words');
var btn = document.getElementById('btn');
var text = words.value;
if(!text){
btn.disabled = true;
}else{
btn.disabled = false;
}
}
function submitHandler(){
//Your code here
alert("submitted");
return false;
}
</script>
How would I go about preventing the page from refreshing when pressing the send button without any data in the fields?
The validation is setup working fine, all fields go red but then the page is immediately refreshed. My knowledge of JS is relatively basic.
In particular I think the processForm() function at the bottom is 'bad'.
HTML
<form id="prospects_form" method="post">
<input id="form_name" tabindex="1" class="boxsize" type="text" name="name" placeholder="Full name*" maxlength="80" value="" />
<input id="form_email" tabindex="2" class="boxsize" type="text" name="email" placeholder="Email*" maxlength="100" value="" />
<input id="form_subject" class="boxsize" type="text" name="subject" placeholder="Subject*" maxlength="50" value="FORM: Row for OUBC" />
<textarea id="form_message" class="boxsize" name="message" placeholder="Message*" tabindex="3" rows="6" cols="5" maxlength="500"></textarea>
<button id="form_send" tabindex="5" class="btn" type="submit" onclick="return processForm()">Send</button>
<div id="form_validation">
<span class="form_captcha_code"></span>
<input id="form_captcha" class="boxsize" type="text" name="form_captcha" placeholder="Enter code" tabindex="4" value="" />
</div>
<div class="clearfix"></div>
</form>
JS
$(document).ready(function() {
// Add active class to inputs
$("#prospects_form .boxsize").focus(function() { $(this).addClass("hasText"); });
$("#form_validation .boxsize").focus(function() { $(this).parent().addClass("hasText"); });
// Remove active class from inputs (if empty)
$("#prospects_form .boxsize").blur(function() { if ( this.value === "") { $(this).removeClass("hasText"); } });
$("#form_validation .boxsize").blur(function() { if ( this.value === "") { $(this).parent().removeClass("hasText"); } });
///////////////////
// START VALIDATION
$("#prospects_form").ready(function() {
// DEFINE GLOBAL VARIABLES
var valName = $('#form_name'),
valEmail = $("#form_email"),
valEmailFormat = /^(([^<>()[\]\\.,;:\s#\"]+(\.[^<>()[\]\\.,;:\s#\"]+)*)|(\".+\"))#((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/,
valMsg = $('#form_message'),
valCaptcha = $('#form_captcha'),
valCaptchaCode = $('.form_captcha_code');
// Generate captcha
function randomgen() {
var rannumber = "";
// Iterate through 1 to 9, 4 times
for(ranNum=1; ranNum<=4; ranNum++){ rannumber+=Math.floor(Math.random()*10).toString(); }
// Apply captcha to element
valCaptchaCode.html(rannumber);
}
randomgen();
// CAPTCHA VALIDATION
valCaptcha.blur(function() {
function formCaptcha() {
if ( valCaptcha.val() == valCaptchaCode.html() ) {
// Incorrect
valCaptcha.parent().addClass("invalid");
return false;
} else {
// Correct
valCaptcha.parent().removeClass("invalid");
return true;
}
}
formCaptcha();
});
// Remove invalid class from captcha if typing
valCaptcha.keypress(function() {
valCaptcha.parent().removeClass("invalid");
});
// EMAIL VALIDATION (BLUR)
valEmail.blur(function() {
function formEmail() {
if (!valEmailFormat.test(valEmail.val()) && valEmail.val() !== "" ) {
// Incorrect
valEmail.addClass("invalid");
} else {
// Correct
valEmail.removeClass("invalid");
}
}
formEmail();
});
// Remove invalid class from email if typing
valEmail.keypress(function() {
valEmail.removeClass("invalid");
});
// VALIDATION ON SUBMIT
$('#prospects_form').submit(function() {
console.log('user hit send button');
// EMAIL VALIDATION (SUBMIT)
function formEmailSubmit() {
if (!valEmailFormat.test(valEmail.val())) {
// Incorrect
valEmail.addClass("invalid");
} else {
// Correct
valEmail.removeClass("invalid");
}
}
formEmailSubmit();
// Validate captcha
function formCaptchaSubmit() {
if( valCaptcha.val() === valCaptchaCode.html() ) {
// Captcha is correct
} else {
// Captcha is incorrect
valCaptcha.parent().addClass("invalid");
randomgen();
}
}
formCaptchaSubmit();
// If NAME field is empty
function formNameSubmit() {
if ( valName.val() === "" ) {
// Name is empty
valName.addClass("invalid");
} else {
valName.removeClass("invalid");
}
}
formNameSubmit();
// If MESSAGE field is empty
function formMessageSubmit() {
if ( valMsg.val() === "" ) {
// Name is empty
valMsg.addClass("invalid");
} else {
valMsg.removeClass("invalid");
}
}
formMessageSubmit();
// Submit form (if all good)
function processForm() {
if ( formEmailSubmit() && formCaptchaSubmit() && formNameSubmit() && formMessageSubmit() ) {
$("#prospects_form").attr("action", "/clients/oubc/row-for-oubc-send.php");
$("#form_send").attr("type", "submit");
return true;
} else if( !formEmailSubmit() ) {
valEmail.addClass("invalid");
return false;
} else if ( !formCaptchaSubmit() ) {
valCaptcha.parent().addClass("invalid");
return false;
} else if ( !formNameSubmit() ) {
valName.addClass("invalid");
return false;
} else if ( !formMessageSubmit() ) {
valMsg.addClass("invalid");
return false;
} else {
return false;
}
}
});
});
// END VALIDATION
/////////////////
});
You can prevent the form from submitting with
$("#prospects_form").submit(function(e) {
e.preventDefault();
});
Of course, in the function, you can check for empty fields, and if anything doesn't look right, e.preventDefault() will stop the submit.
Without jQuery:
var form = document.getElementById("myForm");
function handleForm(event) { event.preventDefault(); }
form.addEventListener('submit', handleForm);
Add this onsubmit="return false" code:
<form onsubmit="return false">
That fixed it for me. It will still run the onClick function you specify.
Replace button type to button:
<button type="button">My Cool Button</button>
One great way to prevent reloading the page when submitting using a form is by adding return false with your onsubmit attribute.
<form onsubmit="yourJsFunction();return false">
<input type="text"/>
<input type="submit"/>
</form>
You can use this code for form submission without a page refresh. I have done this in my project.
$(function () {
$('#myFormName').on('submit',function (e) {
$.ajax({
type: 'post',
url: 'myPageName.php',
data: $('#myFormName').serialize(),
success: function () {
alert("Email has been sent!");
}
});
e.preventDefault();
});
});
This problem becomes more complex when you give the user 2 possibilities to submit the form:
by clicking on an ad hoc button
by hitting Enter key
In such a case you will need a function which detects the pressed key in which you will submit the form if Enter key was hit.
And now comes the problem with IE (in any case version 11)
Remark:
This issue does not exist with Chrome nor with FireFox !
When you click the submit button the form is submitted once; fine.
When you hit Enter the form is submitted twice ... and your servlet will be executed twice. If you don't have PRG (post redirect get) architecture serverside the result might be unexpected.
Even though the solution looks trivial, it tooks me many hours to solve this problem, so I hope it might be usefull for other folks.
This solution has been successfully tested, among others, on IE (v 11.0.9600.18426), FF (v 40.03) & Chrome (v 53.02785.143 m 64 bit)
The source code HTML & js are in the snippet. The principle is described there.
Warning:
You can't test it in the snippet because the post action is not
defined and hitting Enter key might interfer with stackoverflow.
If you faced this issue, then just copy/paste js code to your environment and adapt it to your context.
/*
* inForm points to the form
*/
var inForm = document.getElementById('idGetUserFrm');
/*
* IE submits the form twice
* To avoid this the boolean isSumbitted is:
* 1) initialized to false when the form is displayed 4 the first time
* Remark: it is not the same event as "body load"
*/
var isSumbitted = false;
function checkEnter(e) {
if (e && e.keyCode == 13) {
inForm.submit();
/*
* 2) set to true after the form submission was invoked
*/
isSumbitted = true;
}
}
function onSubmit () {
if (isSumbitted) {
/*
* 3) reset to false after the form submission executed
*/
isSumbitted = false;
return false;
}
}
<!DOCTYPE html>
<html>
<body>
<form id="idGetUserFrm" method="post" action="servletOrSomePhp" onsubmit="return onSubmit()">
First name:<br>
<input type="text" name="firstname" value="Mickey">
<input type="submit" value="Submit">
</form>
</body>
</html>
The best solution is onsubmit call any function whatever you want and return false after it.
onsubmit="xxx_xxx(); return false;"
Most people would prevent the form from submitting by calling the event.preventDefault() function.
Another means is to remove the onclick attribute of the button, and get the code in processForm() out into .submit(function() { as return false; causes the form to not submit. Also, make the formBlaSubmit() functions return Boolean based on validity, for use in processForm();
katsh's answer is the same, just easier to digest.
(By the way, I'm new to stackoverflow, give me guidance please. )
In pure Javascript, use: e.preventDefault()
e.preventDefault() is used in jquery but works in javascript.
document.querySelector(".buttonclick").addEventListener("click",
function(e){
//some code
e.preventDefault();
})
The best way to do so with JS is using preventDefault() function.
Consider the code below for reference:
function loadForm(){
var loginForm = document.querySelector('form'); //Selecting the form
loginForm.addEventListener('submit', login); //looking for submit
}
function login(e){
e.preventDefault(); //to stop form action i.e. submit
}
Personally I like to validate the form on submit and if there are errors, just return false.
$('form').submit(function() {
var error;
if ( !$('input').val() ) {
error = true
}
if (error) {
alert('there are errors')
return false
}
});
http://jsfiddle.net/dfyXY/
$("#buttonID").click(function (e) {
e.preventDefault();
//some logic here
}
If you want to use Pure Javascript then the following snippet will be better than anything else.
Suppose:
HTML:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Form Without Submiting With Pure JS</title>
<script type="text/javascript">
window.onload = function(){
/**
* Just Make sure to return false so that your request will not go the server script
*/
document.getElementById('simple_form').onsubmit = function(){
// After doing your logic that you want to do
return false
}
}
</script>
</head>
<body>
</body>
</html>
<form id="simple_form" method="post">
<!-- Your Inputs will go here -->
<input type="submit" value="Submit Me!!" />
</form>
Hope so it works for You!!
Just use "javascript:" in your action attribute of form if you are not using action.
In my opinion, most answers are trying to solve the problem asked on your question, but I don't think that's the best approach for your scenario.
How would I go about preventing the page from refreshing when pressing the send button without any data in the fields?
A .preventDefault() does indeed not refresh the page. But I think that a simple require on the fields you want populated with data, would solve your problem.
<form id="prospects_form" method="post">
<input id="form_name" tabindex="1" class="boxsize" type="text" name="name" placeholder="Full name*" maxlength="80" value="" required/>
<input id="form_email" tabindex="2" class="boxsize" type="text" name="email" placeholder="Email*" maxlength="100" value="" required/>
<input id="form_subject" class="boxsize" type="text" name="subject" placeholder="Subject*" maxlength="50" value="FORM: Row for OUBC" required/>
<textarea id="form_message" class="boxsize" name="message" placeholder="Message*" tabindex="3" rows="6" cols="5" maxlength="500"></textarea>
</form>
Notice the require tag added at the end of each input. The result will be the same: not refreshing the page without any data in the fields.
<form onsubmit="myFunction(event)">
Name : <input type="text"/>
<input class="submit" type="submit">
</form>
<script>
function myFunction(event){
event.preventDefault();
//code here
}
</script>
function ajax_form(selector, obj)
{
var form = document.querySelectorAll(selector);
if(obj)
{
var before = obj.before ? obj.before : function(){return true;};
var $success = obj.success ? obj.success: function(){return true;};
for (var i = 0; i < form.length; i++)
{
var url = form[i].hasAttribute('action') ? form[i].getAttribute('action') : window.location;
var $form = form[i];
form[i].submit = function()
{
var xhttp = new XMLHttpRequest();
xhttp.open("POST", url, true);
var FD = new FormData($form);
/** prevent submiting twice */
if($form.disable === true)
return this;
$form.disable = true;
if(before() === false)
return;
xhttp.addEventListener('load', function()
{
$form.disable = false;
return $success(JSON.parse(this.response));
});
xhttp.send(FD);
}
}
}
return form;
}
Didn't check how it works. You can also bind(this) so it will work like jquery ajaxForm
use it like:
ajax_form('form',
{
before: function()
{
alert('submiting form');
// if return false form shouldn't be submitted
},
success:function(data)
{
console.log(data)
}
}
)[0].submit();
it return nodes so you can do something like submit i above example
so far from perfection but it suppose to work, you should add error handling or remove disable condition
Sometimes e.preventDefault(); works then developers are happy but sometimes not work then developers are sad then I found solution why sometimes not works
first code sometimes works
$("#prospects_form").submit(function(e) {
e.preventDefault();
});
second option why not work?
This doesn't work because jquery or other javascript library not loading properly you can check it in console that all jquery and javascript files are loaded properly or not.
This solves my problem. I hope this will be helpful for you.
I hope this will be the last answer
$('#the_form').submit(function(e){
e.preventDefault()
alert($(this).serialize())
// var values = $(this).serialize()
// logic....
})
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<form id="the_form">
Label-A <input type="text" name='a'required><br>
Label-B <input type="text" name="b" required><br>
Label-C <input type="password" name="c" required><br>
Label-D <input type="number" name="d" required><br>
<input type="submit" value="Save without refresh">
</form>
You can do this by clearing the state as below. add this to very beginning of the document.ready function.
if ( window.history.replaceState ) {
window.history.replaceState( null, null, window.location.href );
}
I've been reading many questions that ask how to call a knockout validation extender on a button click event. But all the answers that come close to answering the question, involve workarounds using the knockout-validate library. I'm not using the knockout-validate library. All I want to do is validate an input field on a button click event using the validation rules defined in a knockout extender.
For simplicity I'm going to use the required extender from the knockout documentation and apply it to a simple use case. This use case takes an input and on a button click event does something with the value the user entered. Or updates the view to show the validation message if no value was entered.
Knockout Code:
ko.extenders.required = function (target, overrideMessage) {
target.hasError = ko.observable();
target.validationMessage = ko.observable();
function validate(value) {
target.hasError(value ? false : true);
target.validationMessage(value ? "" : overrideMessage || 'Value required');
}
return target;
};
function MyViewModel() {
self = this;
self.userInput = ko.observable().extend({ required: 'Please enter a value' });
/**
* Event handler for the button click event
*/
self.processInput = function () {
//Validate input field
//How to call the validate function in the required extender?
//If passes validation, do something with the input value
doSomething(self.userInput());
};
}
Markup:
<input type="text" data-bind="value: userInput, valueUpdate: 'afterkeydown'" />
<span data-bind="visible: userInput .hasError, text: userInput .validationMessage" class="text-red"></span>
<button data-bind="click: processInput ">Do Something</button>
How can I trigger the validation on the button click event and show the validation message if it doesn't pass validation?
I believe you were looking at the example here - http://knockoutjs.com/documentation/extenders.html
You can not call validate directly, but the subscribe watches the value and runs the validate function on change and updates an observable you can check - hasError.
ko.extenders.required = function (target, overrideMessage) {
target.hasError = ko.observable();
target.validationMessage = ko.observable();
function validate(value) {
target.hasError(value ? false : true);
target.validationMessage(value ? "" : overrideMessage || 'Value required');
}
//initial validation
validate(target());
//validate whenever the value changes
target.subscribe(validate);
//return the original observable
return target;
};
function MyViewModel() {
self = this;
self.userInput = ko.observable().extend({ required: 'Please enter a value' });
/**
* Event handler for the button click event
*/
self.processInput = function () {
if(self.userInput.hasError()){
console.log('has error');
}else{
console.log('no error');
}
};
}
// Activates knockout.js
ko.applyBindings(new MyViewModel());
<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.2.0/knockout-min.js"></script>
<input type="text" data-bind="value: userInput, valueUpdate: 'afterkeydown'" />
<span data-bind="visible: userInput .hasError, text: userInput .validationMessage" class="text-red"></span>
<button data-bind="click: processInput ">Do Something</button>
I have page when I have input and a button.
<div>
<div class="input-group">
<span class="input-group-addon">Enter test</span>
<input type="Text" class="form-control" data-bind="value:Test, event: { keypress: searchKeyboardCmd}" required />
</div>
</div>
<button data-bind=' event:{click:foo}' class="btn btn-default">Submit</button>
and my code:
var ViewModel = function () {
var self = this;
self.Test = ko.observable();
self.data = ko.observableArray([]);
self.DeviceId = ko.observable();
self.number = ko.observable(1);
self.MeUser = ko.observable(true);
self.searchKeyboardCmd = function (data, event) {
if (event.keyCode == 13)
alert("Znalazlem enter " + ko.toJSON(self));
return true;
};
self.foo = function () {
alert("foo");
}
};
ko.applyBindings(new ViewModel());
});
And I have problems with my code. I catch enter with this code:
self.searchKeyboardCmd = function (data, event) {
if (event.keyCode == 13)
alert("Znalazlem enter " + ko.toJSON(self));
return true;
};
It's catches perfectly but binded object is updated after calling alert. So in the first enter I null in value Test. After second enter I have first value and so on. Can anyone suggest me how to modify this code?
The problem is that the event is executed before the blur event (which is when the value is updated. You can make sure the update gets updated after every keystroke by adding valueupdate: 'afterkeydown' to the input:
<div>
<div class="input-group">
<span class="input-group-addon">Enter test</span>
<input type="Text" class="form-control"
data-bind="valueUpdate: 'afterkeydown', value:Test, event: { keypress: searchKeyboardCmd}" required />
</div>
</div>
<button data-bind=' event:{click:foo}' class="btn btn-default">Submit</button>
I have decided to create a wizard form in HTML 5 (actually using ASP.NET MVC here). I have the following HTML form:
#using (Html.BeginForm())
{
<div class="wizard-step">
<input type="text" name="firstname" placeholder="first name" />
</div>
<div class="wizard-step">
<input type="text" name="lastname" placeholder="last name" />
</div>
<div class="wizard-step">
<input type="text" name="suffix" placeholder="suffix" />
</div>
<button class="back-button" type="button">
Back</button>
<button class="next-button" type="button">
Next</button>
}
Then I have this js script:
<script type="text/javascript">
$(document).ready(function () {
var $steps = $(".wizard-step");
var index = 0;
var count = $steps.length;
$steps.each(function () {
$(this).hide();
});
$(".back-button").attr("disabled", "disabled");
var $currentStep = $steps.first();
$currentStep.show();
$currentStep.addClass("current-step");
$(".back-button").click(function () {
$currentStep.hide();
$currentStep.removeClass("current-step");
$currentStep = $currentStep.prev();
$currentStep.addClass("current-step");
$currentStep.show();
index--;
$(".next-button").removeAttr("disabled");
if (index == 0) {
$(this).attr("disabled", "disabled");
}
else {
$(this).removeAttr("disabled");
}
});
$(".next-button").click(function () {
var $inputFields = $(".current-step :input");
var hasError = false;
$inputFields.each(function () {
if (!validator.element(this)) {
hasError = true;
}
});
if (hasError)
return false;
index++;
$(".back-button").removeAttr("disabled");
if (index == count - 1) {
$(this).attr("disabled", "disabled");
}
else {
$(this).removeAttr("disabled");
}
$currentStep.hide();
$currentStep.removeClass("current-step");
$currentStep = $currentStep.next();
$currentStep.addClass("current-step");
$currentStep.show();
});
});
</script>
Basically, what I want is upon clicking the Next button, it will validate the input elements found inside the current visible DIV, not the entire FORM. Is it possible to do this using HTML5? If not, maybe jQuery?
If you have others in mind, please do share it here. Many many thanks!
after some playing with the jquery i happened to find the solution despite of lack of samples and tutorials in validation. inside the $(".next-button").click() block, i made these changes:
old:
var hasError = false;
$inputFields.each(function () {
if (!validator.element(this)) {
hasError = true;
}
});
if (hasError)
return false;
new:
var isValid = false;
$inputFields.each(function () {
isValid = $(this).valid();
});
if (!isValid)
return false;
======================
i could also add this right under the $(document).ready() line to use/add jquery validation rules:
$("#myForm").validate({
rules: {
lastname: "required"
}
});