Objective
FrameWork used : ElectronJS
I want to take the user submitted form, and use the NodeJS script to generate a JSON file on client PC. The json file will have key and value pairs.
Please see below for expected output.
HTML
<form id="form" method="POST" action="#">
<div class="form-group col-auto">
<input type="text" class="form-control" id="username" name="username" placeholder="Enter Username" value="">
</div>
<div class="form-group col-auto">
<input type="text" class="form-control" id="account" name="account" placeholder="Enter Account" value="">
</div>
<button type="submit" id="save" class = "btn text-white mb-0"> Save </button>
</form>
JS
document.getElementById("save").addEventListener('click', saveJSON(e))
async function saveJSON(e){
e.preventDefault()
var userData = document.getElementById('username').value
var acctData = document.getElementById('account').value
var formData = userData + acctData;
console.log(formData);
await writer.jsonWriter(formData);
//Error - Uncaught TypeError: Cannot read property 'value' of undefined.
Error
Here is the error I am facing
NodeJS Script
async function jsonWriter(data){
let element = JSON.stringify(data);
fs.writeFileSync(__dirname + '\\data\\auth.json', element)
}
module.exports.jsonWriter = jsonWriter;
Required Output
// auth.json
{"username":"Stack","account":"Overflow"}
I believe there was an issue with how you were passing your event into your function and trying to call preventDefault(). I put your function directly on the event listener method with async keyword.
As previously mentioned, document.querySelector() uses CSS selectors unlike document.getElementById(). In your case I would stick with getting the input elements by their ID.
Like Paul said in his answer, you need a JavaScript object for JSON.stringify() to work properly.
document.getElementById("save").addEventListener('click', async function(e) {
e.preventDefault()
var userData = document.getElementById('username').value
var acctData = document.getElementById('account').value
var formData = {
username: userData,
account: acctData
}; // create JS object
console.log(JSON.stringify(formData));
});
<form id="form" method="POST" action="#">
<input type="text" id="username" name="username" placeholder="Enter Username">
<input type="text" id="account" name="account" placeholder="Enter Account">
<button type="submit" id="save">Save</button>
</form>
Okay I think that I can see your mistake.
In the Javascript you can change this part :
var formData = userData + acctData;
console.log(formData);
await writer.jsonWriter(formData);
To this part :
Try to assign it to a javascript object like that :
var formData = {username: userData, account: acctData};
console.log(formData);
await writer.jsonWriter(formData);
it will stringify your object and write an appropriate output.
I think.
I need each instance of input and submit to operate independently. What is the best way to handle multiple instances where each submit is connected to it's own set of inputs?
Since they are unrelated, would data-attributes be the best solution?
$(document).ready(function() {
validate();
$('input').on('keyup', validate);
});
function validate() {
var inputsWithValues = 0;
var myInputs = $("input:not([type='submit'])");
myInputs.each(function(e) {
if ($(this).val()) {
inputsWithValues += 1;
}
});
if (inputsWithValues == myInputs.length) {
$("input[type=submit]").prop("disabled", false);
} else {
$("input[type=submit]").prop("disabled", true);
}
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="item1">
<div><input type="text" name="name" autocomplete="off" required/></div>
<input type="submit" value="Submit 1" />
</div>
<div class="item2">
<div><input type="text" name="name" autocomplete="off" required/></div>
<div><input type="text" name="name" autocomplete="off" required/></div>
<input type="submit" value="Submit 2" />
</div>
I think your intuition about using data attributes works great here.
var allButtons = document.querySelectorAll("input[type=submit]");
allButtons.forEach(button => {
button.addEventListener("click", () => {
var inputSet = button.getAttribute("data-input-set");
var inputs = document.querySelectorAll("input[type='text'][data-input-set='" + inputSet + "']");
});
});
In the following code, when an input button is pressed, it will fetch all the inputs with the corresponding "input-set" tag.
Preferred way
I think best solution would be use form -tag as it is created for just this use case HTML Forms.
<form id="form-1">
<input type="text"/>
<input type="submit>
</form>
<form id="form-2">
<input type="text"/>
<input type="submit>
</form>
You can also bind custom Form on submit event handlers and collect form data this way.
$('#form-1').on('submit', function(event){
event.preventDefault(); // Prevent sending form as defaulted by browser
/* Do something with form */
});
Possible but more bolt on method
Alternative methods to this would be to create your own function's for collecting all relevant data from inputs and merge some resonable data object.
I would most likely do this with giving desired class -attribute all inputs I would like to collect at once eg. <input type="text" class="submit-1" /> and so on. Get all elements with given class, loop through all them and save values into object.
This requires much more work tho and form -tag gives you some nice validation out of the box which you this way have to do yourself.
I have this code in html.
<form method="POST" data-bind="submit: submitComment">
<label for="comment">
<textarea name="comment" data-bind="value: commentTextArea"></textarea>
<button type="submit">Submit</button>
</label>
</form>
and this is my knockout viewmodel
this.commentTextArea = ko.observable('');
this.submitComment = function(formElement) {
alert("I'm being posted!");
return false;
}
My problem is that when I submit the form the return false; row is ignored, thus submittinig the form "for real". I can verify that I am in the submitComment() method since the alert is fired.
I've read the knockout guide and several examples but no example even say I would need the return false; line.
The goal is to prevent the event from bubble. Thanks
I solved it by changing the data-bind-type to an event like this
<form method="POST" data-bind="event: { submit: submitComment }">
<label for="comment">
<textarea name="comment" data-bind="value: commentTextArea"></textarea>
<button type="submit">Submit</button>
</label>
</form>
By changing to an event I get the event-parameter that I use to stop propagating like this
this.commentTextArea = ko.observable('');
this.submitComment = function(formElement, event) {
event.stopPropagation();
}
I have an HTML form that I would like to make interact with some JavaScript:
...
<form name="signup">
<label id="email" for="email" placeholder="Enter your email...">Email: </label>
<input type="email" name="email" id="email" />
<br />
<input type="submit" name="submit" id="submit" value="Signup" onclick="signup()"/>
</form>
...
I have some JavaScript that I want to take the entered email address and store it in an array (it is currently inline with my HTML hence the script tags):
<script type="text/javascript" charset="utf-8">
var emailArray = [];
function signup(){
var email = document.signup.email.value;
emailArray.push(email);
alert('You have now stored your email address');
window.open('http://google.com');
console.log(emailArray[0]);
}
</script>
I was hoping that this simple script would store the email in emailArray but the console remains empty throughout the execution.
What is wrong with this code?
You have two problems.
Your form is named signup and your global function is named signup. The function is overwritten by a reference to the HTML Form Element Node.
Your submit button will submit the form, causing the browser to leave the page as soon as the JS has finished (discarding all the stored data and probably erasing the console log)
Rename the function and add return false; to the end of your event handler function (the code in the onclick attribute.
Please rename your function name (signup) or Form Name (signup),
because when you are try to access document.signup......
It'll make a type error like, object is not a function
Try below Code,
<script type="text/javascript">
var emailArray = [];
function signup() {
var theForm = document.forms['signupForm'];
if (!theForm) {
theForm = document.signupForm;
}
var email = theForm.email.value;
emailArray.push(email);
console.log(emailArray[0]);
}
</script>
<form name="signupForm">
<label id="email" for="email" placeholder="Enter your email...">Email: </label>
<input type="email" name="email" id="email" />
<br />
<input type="button" name="submit" id="submit" value="Signup" onclick="signup(); return false;"/>
</form>
The problem that is given is that the form name is "signup" and the function is "signup()", then the function is never executed (this is better explained in this answer). If you change your form name or your function name everything should work as expected.
try this code :
<form name="test">
<label id="email" for="email" placeholder="Enter your email...">Email: </label>
<input type="text" name="email" id="email" onBlur=/>
<br />
<input type="button" name="submit" id="submit" value="Signup" onclick="signup()"/>
</form>
<script type="text/javascript" charset="utf-8">
var emailArray = [];
function signup(){
var email = document.getElementById('email').value;
emailArray.push(email);
alert('You have now stored your email address');
window.open('http://google.com');
console.log(emailArray[0]);
return false;
}
</script>
As suggested in the comments, just change your email variable to:
var email = document.getElementById('email').value;
then just push it to your emailArray
EDIT
You'll need to rename the ID of your label. The reason it's currently not working is because the value being returned is that of the first element with the id of email (which is your label, and undefined).
Here's a Fiddle
I would propose two improvements to your code:
Put your javascript right after the <form> element in order to be sure that dom element exist in the document
Attach click handler using addEventListener method. Read more here.
Email:
var emailArray = []; function signup(){ var email = document.getElementById('email').value; emailArray.push(email); alert('You have now stored your email address'); window.open('http://google.com'); console.log(emailArray[0]); return false; } document.getElementById("submit").addEventHandler('click', signup, false);
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);
}
});