Cold calling blur() function in JavaScript - javascript

I have a line
document.getElementById("firstName").addEventListener("blur", validateField);
and :
validateField = (event) =>
{
const el = event.target;
}
Now I want to call the validateField() function with the respective element in the form.addEventListener('submit', function(event) line.
document.getElementById("firstName").blur(); // This is not getting called.
But cold-calling blur() isn't working.
What I am trying to do is to populate the bootstrap is-invalid message when the form is called and still invalid.
el.classList.add('is-invalid');
el.nextElementSibling.innerHTML = "This field is required";
Trying to avoid jQuery as I may switch this over to bootstrap version 5.

I do think technically, submitting form unfocuses, unless the user presses the enter key to submit. An alternate approach is maybe, you can try to focus on something else than blurring a particular thing!
The following code works for me.
document.getElementById("frm").addEventListener('submit', function(event) {
event.preventDefault();
document.getElementById("firstName").blur();
});
<form action="" id="frm">
<input type="text" id="firstName" />
<input type="submit" value="Press Enter" />
</form>
But for the alternate solution:
document.getElementById("frm").addEventListener('submit', function(event) {
event.preventDefault();
document.getElementById("frm").focus();
});
#frm:focus {
outline: none;
box-shadow: none;
}
<form action="" id="frm" tabindex="0">
<input type="text" id="firstName" />
<input type="submit" value="Press Enter" />
</form>

Related

How to hit "Esc" key as well when clicking the type="reset" button?

Is there a way to trigger the hitting of "Esc" key as well when clicking the <input type="reset"> button? ( For some reason, the existing function needs Esc to work properly. )
To be precise, the desired result is:
Typing in the input field
Click "Reset"
Clear input + Hitting the "Esc" key
Here is the form created for example:
<script src="https://cdn.jsdelivr.net/npm/jquery#3.2.1/dist/jquery.min.js"></script>
<form onsubmit="event.preventDefault(); myFunction();">
<input type="text" id="quick-search" required="" />
<input type="reset" id="reset-btn" value="Reset" />
</form>
<style>
input#quick-search:not(:valid)~input#reset-btn {
display: none;
}
</style>
<script>
$(document).keydown(function(e) {
if (e.key === "Escape") {
$("#reset-btn").click();
}
});
</script>
I know how to make "Esc" as clicking reset, but cannot find the answer to make clicking reset also comes with a hit on "Esc".
$(document).on('keyup', function(event) {
if (event.key == "Escape") {
$("#reset-btn").click();
}
});
input#quick-search:not(:valid)~input#reset-btn {
display: none;
}
<script src="https://cdn.jsdelivr.net/npm/jquery#3.2.1/dist/jquery.min.js"></script>
<form onsubmit="event.preventDefault(); myFunction();">
<input type="text" id="quick-search" required="" />
<input type="reset" id="reset-btn" value="Reset" />
</form>
Thanks for the comment on the question.
The script turns out be like this:
var esc = jQuery.Event("keypress");
esc.keyCode = 27;
$("#reset-btn").trigger(esc);
Ref: https://stackoverflow.com/a/55102965/1468253

Why's my form action still being triggered when validating the form despite using e.preventDefault()?

I'd like to display a message above the name field if the user submits a name with a length greater than 20. This means the form will not get submitted - in other words, the form's action won't be triggered.
I've tried almost every suggestion I could find to prevent the form action from being triggered upon form validation but nothing seems to be working.
I've hit a wall with this and can't figure out what I'm doing wrong. How can rectify this?
html:
<form method="POST" id="form" action="/post.php">
<span class="nameError"></span>
<input type="text" class="name" name="name" placeholder="Name" required/>
<input class="button" type="submit" value="Submit"/>
</form>
Here's my jquery:
let name = $('.name');
let nameError= $('.nameError');
$(document).ready(function() {
$('input[type=submit]').on('click', function(e) {
if (name.length > 20) {
e.preventDefault();
nameError.val("Too many characters!");
return false;
}
});
});
I have modified the logic for validation. Basically we need to capture the submit event for the form and use the correct jquery methods to retreive data based upon the selectors.
$(document).ready(function() {
$("#form").submit(function( event ) {
let name = $('.name').val();
let nameError= $('.nameError');
if (name.length > 20) {
nameError.text("Too many characters!");
event.preventDefault();
}
});
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.2/jquery.min.js"></script>
<form method="POST" id="form" action="/post.php">
<input type="text" class="name" name="name" placeholder="Name" required/>
<label class="nameError"></label> <br/>
<input class="button" type="submit" value="Submit"/>
</form>

Check if all the required inputs are set before submit with javascript

I'm wondering if there's a way to force a check for the required inputs on a form before submitting it programmatically using pure Javascript:
<form method="post" action="myController.php" id="myForm">
<input type="text" id="input1" required>
<input type="text" id="input2" required>
<input type="text" id="input3" required>
<input type="submit" onClick="return checkForm(event)" value="Save">
</form>
My Javascript file:
function checkForm(e) {
e.preventDefault();
// Some other stuff
/*Prevalidate required inputs here*/
document.getElementById('myForm').submit();
}
I'm wondering if there's something like:
if(document.getElementById('myForm').valid()) {
document.getElementById('myForm').submit()
}
Where the required inputs are checked just before submitting the form without the need to verify one by one directly by code.
There is the form.onSubmit event
But if you are using HTML 5, you can use input.pattern with a regular expression; submission will be blocked if the input doesn't pass the check and the input element will (on many browsers) get a red border around it.
If you need to do something custom on submit you can trigger validation via form.reportValidity() and get back a boolean indicating whether all inputs have satisfied their constraints.
You can also listen for invalid events that will get fired for each invalid input during validation if you want to do something to flag them in the UI:
function onInvalid (e) {
e.target.classList.add('invalid');
}
const form = document.querySelector('form');
document.querySelectorAll('input').forEach(input => {
input.addEventListener('invalid', onInvalid);
});
form.addEventListener('submit', (e) => {
e.preventDefault();
const valid = form.reportValidity();
})
.invalid {
border: 4px solid red;
}
<form>
<input name="test1" required />
<input name="test2" required />
<input name="test3" required />
<input type="submit" />
</form>
Take adventage of Form attribute onsumbit to submit the form if the value returned from the function checkForm which returns boolean value if all fields are filled and not empty dynamically.
function checkForm(e) {
let valid = true;
inputs = document.querySelectorAll('[type="text"]')
for(input of inputs){
if(input.value.trim()==''){
valid = false;
break;
}
}
return valid;
}
<form method="post" id="myForm" action='test.php' onsubmit="return checkForm(this)">
<input type="text" id="input1" required>
<input type="text" id="input2" required>
<input type="text" id="input3" required>
<input type="submit" value="Save">
</form>

Textbox values are cleared after function ends (Issue): JQuery

I have below code to set fullName value, logic works but after it sets the value all the textbox values are cleared. I need overcome this issue.
<script>
$(document).ready(function() {
$('#check').click(function() {
if ( $('#city').val() == '' )
{
alert('Empty!!!');
}
else
{
$('#fullName').val("hi");
}
});
});
</script>
<form name="form1" method="post" action="">
City: <input type="text" name="city" id="city"><br>
Last name: <input type="text" name="LastName" value="Mouse"><br>
Full name: <input type="text" name="fullName" id="fullName"><br>
Phone number: <input type="text" name="Last" value="Mouse"><br>
<button id="check">Check</button>
</form>
By default a button within a form but with no type is a submit button. My guess is you are actually submitting the form when you click the button, and the inputs are 'cleared' because a new page is loading.
Try adding type="button" to your button.
<button id="check" type="button">Check</button>
Use PreventDefault() to cancel postback, becouse your button does not have type so HTML put the default behavior like submit, try:
$('#check').click(function(e) {
e.preventDefault();
if ( $('#city').val() == '' )
{
alert('Empty!!!');
}
else
{
$('#fullName').val("hi");
}
});
LIVE DEMO

Can I determine which Submit button was used in javascript?

I have a very simple form with a name field and two submit buttons: 'change' and 'delete'. I need to do some form validation in javascript when the form is submitted so I need to know which button was clicked. If the user hits the enter key, the 'change' value is the one that makes it to the server. So really, I just need to know if the 'delete' button was clicked or not.
Can I determine which button was clicked? Or do I need to change the 'delete' button from a submit to a regular button and catch its onclick event to submit the form?
The form looks like this:
<form action="update.php" method="post" onsubmit="return checkForm(this);">
<input type="text" name="tagName" size="30" value="name goes here" />
<input type="hidden" name="tagID" value="1" />
<input type="submit" name="submit" value="Change" />
<input type="submit" name="submit" value="Delete" />
</form>
In the checkForm() function, form["submit"] is a node list, not a single element I can grab the value of.
Here's an unobtrusive approach using jQuery...
$(function ()
{
// for each form on the page...
$("form").each(function ()
{
var that = $(this); // define context and reference
/* for each of the submit-inputs - in each of the forms on
the page - assign click and keypress event */
$("input:submit", that).bind("click keypress", function ()
{
// store the id of the submit-input on it's enclosing form
that.data("callerid", this.id);
});
});
// assign submit-event to all forms on the page
$("form").submit(function ()
{
/* retrieve the id of the input that was clicked, stored on
it's enclosing form */
var callerId = $(this).data("callerid");
// determine appropriate action(s)
if (callerId == "delete") // do stuff...
if (callerId == "change") // do stuff...
/* note: you can return false to prevent the default behavior
of the form--that is; stop the page from submitting */
});
});
Note: this code is using the id-property to reference elements, so you have to update your markup. If you want me to update the code in my answer to make use of the name-attribute to determine appropriate actions, let me know.
You could also use the onclick event in a number of different ways to address the problem.
For instance:
<input type="submit" name="submit" value="Delete"
onclick="return TryingToDelete();" />
In the TryingToDelete() function in JavaScript, do what you want, then return false if do not want the delete to proceed.
Some browsers (at least Firefox, Opera and IE) support this:
<script type="text/javascript">
function checkForm(form, event) {
// Firefox || Opera || IE || unsupported
var target = event.explicitOriginalTarget || event.relatedTarget ||
document.activeElement || {};
alert(target.type + ' ' + target.value);
return false;
}
</script>
<form action="update.php" method="post" onsubmit="return checkForm(this, event);">
<input type="text" name="tagName" size="30" value="name goes here" />
<input type="hidden" name="tagID" value="1" />
<input type="submit" name="submit" value="Change" />
<input type="submit" name="submit" value="Delete" />
</form>
For an inherently cross-browser solution, you'll have to add onclick handlers to the buttons themselves.
<html>
<script type="text/javascript">
var submit;
function checkForm(form)
{
alert(submit.value);
return false;
}
function Clicked(button)
{
submit= button ;
}
</script>
<body>
<form method="post" onsubmit="return checkForm(this);">
<input type="text" name="tagName" size="30" value="name goes here" />
<input type="hidden" name="tagID" value="1" />
<input onclick="Clicked(this);" type="submit" name="submit" value="Change" />
<input onclick="Clicked(this);" type="submit" name="submit" value="Delete" />
</form>
</body>
</html>
You could use the SubmitEvent.submitter property.
form.addEventListener('submit', event => console.log(event.submitter))
Give each of the buttons a unique ID such as
<input type="submit" id="submitButton" name="submit" value="Change" />
<input type="submit" id="deleteButton" name="submit" value="Delete" />
I'm not sure how to do this in raw javascript but in jquery you can then do
$('#submitButton').click(function() {
//do something
});
$('#deleteButton').click(function() {
//do something
});
This says that if submitButton is clicked, do whatever is inside it.
if deleteButton is clicked, do whatever is inside it
In jQuery you can use $.data() to keep data in scope - no need for global variables in that case.
First you click submit button, then (depending on it's action) you assign data to form. I'm not preventing default action in click event, so form is submitted right after click event ends.
HTML:
<form action="update.php" method="post"">
<input type="text" name="tagName" size="30" value="name goes here" />
<input type="hidden" name="tagID" value="1" />
<input type="submit" name="submit" value="Change" />
<input type="submit" name="submit" value="Delete" />
</form>
JavaScript:
(function ($) {
"use strict";
$(document).ready(function () {
// click on submit button with action "Change"
$('input[value="Change"]').on("click", function () {
var $form = $(this).parents('form');
$form.data("action", "Change");
});
// click on submit button with action "Delete"
$('input[value="Delete"]').on("click", function () {
var $form = $(this).parents('form');
$form.data("action", "Delete");
});
// on form submit
$('form').on("submit", function () {
var $self = $(this);
// retrieve action type from form
// If there is none assigned, go for the default one
var action = $self.data("action") || "deafult";
// remove data so next time you won't trigger wrong action
$self.removeData("action");
// do sth depending on action type
if (action === "change") {
}
});
});
})(jQuery);
Right now you've got the same problem as you would a normal text input. You've got the same name on two different elements. Change the names to "Change" and "Delete" and then determine if either one of them were clicked by applying an event handler on both submits and providing different methods. I'm assuming you're using pure JavaScript, but if you want it to be quick, take a look at jQuery.
What you need is as simple as following what's on w3schools
Since you didn't mention using any framework, this is the cleanest way to do it with straight Javascript. With this code what you're doing is passing the button object itself into the go() function. You then have access to all of the button's properties. You don't have to do anything with setTimeout(0) or any other wacky functions.
<script type="text/javascript">
function go(button) {
if (button.id = 'submit1')
//do something
else if (button.id = 'submit2')
//do something else
}
</script>
<form action="update.php" method="post">
<input type="text" name="tagName" size="30" value="name goes here" />
<input type="hidden" name="tagID" value="1" />
<input id="submit1" type="submit" name="submit" value="Change" onclick="go(this);"/>
<input id="submit2" type="submit" name="submit" value="Delete" onclick="go(this);"/>
</form>
A click event anywhere in a form will be caught by a form's click handler (as long as the element clicked on allows it to propagate). It will be processed before the form's submit event.
Therefore, one can test whether the click target was an input (or button) tag of the submit type, and save the value of it (say, to a data-button attribute on the form) for processing in the form's submit handler.
The submit buttons themselves do not then need any event handlers.
I needed to do this to change a form's action and target attributes, depending upon which submit button is clicked.
// TO CAPTURE THE BUTTON CLICKED
function get_button(){
var oElement=event.target;
var oForm=oElement.form;
// IF SUBMIT INPUT BUTTON (CHANGE 'INPUT' TO 'BUTTON' IF USING THAT TAG)
if((oElement.tagName=='INPUT')&&(oElement.type=='submit')){
// SAVE THE ACTION
oForm.setAttribute('data-button',oElement.value);
}
}
// TO DO THE SUBMIT PROCESSING
function submit_form(){
var oForm=event.target;
// RETRIEVE THE BUTTON CLICKED, IF ONE WAS USED
var sAction='';
if(oForm.hasAttribute('data-button')){
// SAVE THE BUTTON, THEN DELETE THE ATTRIBUTE (SO NOT USED ON ANOTHER SUBMIT)
sAction=oForm.getAttribute('data-button');
oForm.removeAttribute('data-button');
}
// PROCESS BY THE BUTTON USED
switch(sAction){
case'Change':
// WHATEVER
alert('Change');
break;
case'Delete':
// WHATEVER
alert('Delete');
break;
default:
// WHATEVER FOR ENTER PRESSED
alert('submit: By other means');
break;
}
}
<form action="update.php" method="post" onsubmit="submit_form();" onclick="get_button();">
<input type="text" name="tagName" size="30" value="name goes here" />
<input type="hidden" name="tagID" value="1" />
<input type="submit" name="submit" value="Change" />
<input type="submit" name="submit" value="Delete" />
</form>
<p id="result"></p>
Here is my solution:
Just add dataset in submit button like this:
<form action="update.php" method="post" onsubmit="return checkForm(this);">
<input type="text" name="tagName" size="30" value="name goes here" />
<input type="hidden" name="tagID" value="1" />
<input type="submit" name="submit" value="Change" data-clicked="change" />
<input type="submit" name="submit" value="Delete" data-clicked="delete" />
</form>
In JS access it by:
$('body').on("submit", function(event){
var target = event.explicitOriginalTarget || event.relatedTarget || document.activeElement || {};
var buttonClicked = target.dataset['clicked'];
console.log(buttonClicked);
});
Name the delete button something else. Perhaps name one SubmitChange and name the other SubmitDelete.
I've been dealing with this problem myself. There's no built-in way to tell which button's submitting a form, but it's a feature which might show up in the future.
The workaround I use in production is to store the button somewhere for one event loop on click. The JavaScript could look something like this:
function grabSubmitter(input){
input.form.submitter = input;
setTimeout(function(){
input.form.submitter = null;
}, 0);
}
... and you'd set an onclick on each button:
<input type="submit" name="name" value="value" onclick="grabSubmitter(this)">
click fires before submit, so in your submit event, if there's a submitter on your form, a button was clicked.
I'm using jQuery, so I use $.fn.data() instead of expando to store the submitter. I have a tiny plugin to handle temporarily setting data on an element that looks like this:
$.fn.briefData = function(key, value){
var $el = this;
$el.data(key, value);
setTimeout(function(){
$el.removeData(key);
}, 0);
};
and I attach it to buttons like this:
$(':button, :submit').live('click', function () {
var $form = $(this.form);
if ($form.length) {
$form.briefData('submitter', this);
}
});

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