Why isnt my javascript function being run? - javascript

I'm trying to create a log-in page that validates data before it gets submitted to my php page that handles it. I'm using javascript to validate. This is my code:
<div class = mainInfo>
<?php include "header.php"; ?>
<form name = SignUpForm action = signUpHandler.php method ='POST' class = inputLists>
username: <input type = text name = "userName">
password: <input id= "p1" type = password name = "password">
reenter password: <input id ="p2" type = password name = "passwordConfirmation">
<input type="submit" name =" submitButton" value ="submit">
</form>
<div id="feedback">
</div>
</div>
<script>
function validate()
{
document.getElementById("feedback").innerHTML = "functionbeingcalled";
var p1 = document.getElementById("p1").value,
p2 = document.getElementById("p2").value);
if( ! p1===p2 )
{
document.getElementById("feedback").innerHTML = "passwords dont match";
}
if(p1==="")
{
document.getElementById("feedback").innerHTML = "Must have a password";
}
}
window.setInterval(validate(),1000);
</script>
<?php include "footer.php"; ?>
I would've thought that this script should run every second from the time that the page loads, but the script isn't being run at all. This line:
document.getElementById("feedback").innerHTML = "functionbeingcalled";
isn't working either.
Besides for this question, is it possible to validate data before submitting using only php? I'm new to web programming.

Pass the function instead of calling it.
// no parentheses!
window.setInterval(validate, 1000);
And this is wrong.
if( ! p1===p2 )
it should be this
if( p1!==p2 )
because of the higher precedence of the prefix !

I would suggest that you add listeners on your input fields! ;)
It will then only run the validation code when changes are made. In other words; only when necessary.
It will run the validation code "immediately" when input is changes. Instead of validation every 1000 ms.
I see you are not using jQuery (yet)? If you want to validate on 'change' using plain js, here is a solution: Plain js solution
If you are okay with adding the jQuery library to you code, then it can be done very easy like this jQuery solution

Well, you've got several issues...
First, with setInterval(), you only pass a reference to the function that should be called (validate in your case), you don't actually invoke it as you are doing (validate()). This essentially runs validate immediately and then sets the return value from it as the function to be called every second. Since validate() doesn't return a value, nothing happens every second thereafter.
You also have a typo with: if( ! p1===p2 ), which indicates that the Boolean opposite of p1 is being tested against p2. What you want is: if(p1 !== p2 ), which is how you express "not strictly equal to".
Now, really you are going about validation the wrong way. Instead of running a validation function on a timer, which is inefficient, you'd want to validate in one or more of these cases:
just before the entire form is submitted
just after the user leaves a form field
as the user is entering data
some combination of all 3
Each of those scenarios is handled through event handlers and a working example of each is shown below.
// Get the DOM references you'll need just once:
var feedback = document.getElementById("feedback");
// Don't set variables equal to property values of DOM elements because
// if you decide you need a different property value, you have to re-scan
// the DOM for the same element all over again.
var p1 = document.getElementById("p1")
var p2 = document.getElementById("p2");
var form = document.querySelector("form");
// Use this to validate when submit is pressed (causing form to be submitted):
form.addEventListener("submit", function(evt){
// If validate function returns false, don't submit
if(!validate()){
evt.preventDefault(); // cancel the form submission
feedback.textContent = "Can't submit. Form is not valid!";
}
});
// Get the elements that need to be validated:
var inputs = document.querySelectorAll("input[type=text],input[type=password]");
// Convert that node list into an array:
inputs = Array.prototype.slice.call(inputs);
// Loop over array and set up event handlers for inputs
inputs.forEach(function(input){
input.addEventListener("blur", validate); // Used to validate when user moves off of each element
input.addEventListener("input", validate); // Used to validate as data is being entered
});
function validate() {
// Keep track of whether the form is valid or not. Assume that it is by default
var valid = true;
// .innerHTML is for when you want to assign a string containing
// HTML to a DOM element. This invokes the HTML parser and renders
// the HTML. If you don't have HTML in the string, use .textContent
// instead, which doesn't invoke the HTML parser and is more efficient
// See if the password was typed in both boxes before telling the user
// that the passwords don't match
if(p1.value && p2.value){
// Are they the same?
if(p1.value !== p2.value){
feedback.textContent = "passwords dont match";
valid = false;
} else {
feedback.textContent = "passwords match";
}
} else {
// If both password fields aren't filled in, the form can't be valid
valid = false;
}
if(p1.value === "") {
feedback.textContent = "Must have a password";
valid = false;
}
// Send a result to the caller so it can be known by other code if the form is valid
return valid;
}
<div class = "mainInfo">
<form name="SignUpForm" action="signUpHandler.php" method='POST' class="inputLists">
<div>username: <input type="text" name="userName"></div>
<div>password: <input id="p1" type="password" name="password"></div>
<div>reenter password: <input id="p2" type="password" name="passwordConfirmation"></div>
<!-- Any form element that has a "name" attribute will submit its name/value as
part of the form data when the form gets submitted. You probably don't want
the actual submit button to be included in this, so don't give the button
a "name" attribute. -->
<input type="submit" value="submit"> <input type="reset" value="reset">
</form>
<div id="feedback"></div>
</div>

Related

JavaScript Login Form Not Validating

Good Evening,
I am trying to create a simple JavaScript login form that will validate by checking only 1 specific email address which has been declared and 1 password that has been declared.
However, no matter what is typed into the fields, even if nothing is present, once the submit button is clicked, the user is directed to the desired page.
I need it to only allow the desired page if the email address and password are the correct. Otherwise, notify them that it is incorrect.
Here is a link to [codepen][1] so you can see the page and script.
https://codepen.io/m0rrisim0/pen/bmzyqj
Any help is appreciated in figuring out why the script is not validating.
You have to use the attribute value from document.getElementById method,
like the following example: document.getElementById("UserName").value
function validate() {
'use strict';
var UserName = document.getElementById('UserName').value;
var email = "adrian#tissue.com";
var Password = document.getElementById('Password').value;
var pass = "welcome1";
if ((UserName == email) && (Password == pass)) {
return true;
} else {
alert("UserName and/or Password Do Not Match");
return false;
}
}
Your form's inputs lack the id atrribute and should return the function on submit event.
<form action="Issues.html" method="post" id="loginform" onsubmit="return validate()">
UserName:
<input type="text" name="UserName" id="UserName">
<br>
<br>
Password:
<input type="password" name="Password" id="Password">
<hr>
<input type="submit" value="Submit">
</form>
Your problem was getElementById(), this function requires a argument and cause a error. Because of this error the line loginform.onsubmit = validate; was never reached so the submit button submit the form without calling a validate function.
There is no need to put this line inside the if statement, but if you want you can change a little bit to getElementById without the parentesis, this way it evaluates to a function that in js is truthy.
You can check a working version of you code here:
if (document && document.getElementById) {
var loginform = document.getElementById('loginform');
loginform.onsubmit = validate;
}
https://codepen.io/francispires/pen/mzvYKX
You can improve this validation

Javascript email validation failing on a valid email address?

I seem to be unable to get a basic javascript email validation function to work correctly. It keeps returning that the email address is invalid even when using a real email address.
Could someone please point me in the right direction as i couldn't find the problem on any other similar SO posts. I don't think it's the function itself, but perhaps how i am calling it? I have posted the code below.
// E-mail validation via regular expression - taken from SO solution
// Needs to be accessible for other Forms to use
function isValidEmailAddress(emailAddress) {
var pattern = new RegExp(/^((([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+(\.([a-z]|\d|[!#\$%&'\*\+\-\/=\?\^_`{\|}~]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])+)*)|((\x22)((((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(([\x01-\x08\x0b\x0c\x0e-\x1f\x7f]|\x21|[\x23-\x5b]|[\x5d-\x7e]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(\\([\x01-\x09\x0b\x0c\x0d-\x7f]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF]))))*(((\x20|\x09)*(\x0d\x0a))?(\x20|\x09)+)?(\x22)))#((([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|\d|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.)+(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])|(([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])([a-z]|\d|-|\.|_|~|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])*([a-z]|[\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF])))\.?$/i);
return pattern.test(emailAddress);
};
// Validate Contact Form
function validate_contact(evt) {
var error = '';
// Set Veriables
var email = document.getElementById("contact_email");
// Validate Other Fields Here
// - Removed for Example -
// Validate Email Address
if (!isValidEmailAddress(email)) {
error += '- Please enter a valid Email Address.\n';
}
// Show Error Notice
if (error != '') {
error = 'The form has not been completed correctly, please check the following:\n\n' + error;
alert(error);
evt.preventDefault(); // Stop the event
} else {
// Proceed
}
}
// Get reference DOM elements
var contact_form = document.getElementById("contact_form");
// Set up event - Contact Form Validation
contact_form.addEventListener("submit", validate_contact);
// Set up event - Other Form Validation
//other_form.addEventListener("submit", validate_other);
<form id="contact_form" method="post" action="" autocomplete="off">
<input type="text" id="contact_email" name="email" value="">
<input type="submit" id="submit">
</form>
You should do some basic debugging. Look at the contents of the variables you are testing.
var email = document.getElementById("contact_email");
The value of email is the input element, not the text entered into it. For that you need to read its .value property.
Solution is to add ".value"
var email = document.getElementById("contact_email").value;

Forcing a change in the value of the hidden field before submitting a form

I am trying to change the value of a hidden field on submission by JavaScript. In my page there are two buttons, one for going back to homepage (index.php) and another for returning to the first page for data entry (addData.php). I am trying to use a hidden field with id "goHome" to control the routeing. My codes are like this:
HTML (Form only)
<form name = "addDataReal" id = "addDataReal" method = "POST" action = "addDataProc.php" onsubmit="return checkNSub()">
<!-- Other items -->
<input type = "submit" name = "submitBtnF" id = "submitBtnF" class="shortText" style = "width: 120px;" value = "Submit + Home" onclick = "return getGoValue(true)"/>
<input type = "submit" name = "submitBtnR" id = "submitBtnT" class="shortText" style = "width: 120px;" value = "Submit + Next" onclick = "return getGoValue(false)"/>
<input type = "hidden" name = "goHome" id = "goHome" value = "" />
</div>
</form>
Javascript
function checkNSub() {
//form validation functions
//OK then return true
//Not then return false
}
function getGoValue(goHome) {
if (goHome) {
document.getElementById("goHome").value = "true";
} else {
document.getElementById("goHome").value = "false";
}
return true;
}
Before this I have tried many other versions and I refered to these few questions:
Set form hidden value on submit
Setting a form variable value before submitting
How to change the value of hidden input field before submitting
But none of the methods were working for me.
For practical purposes there is a workaround for this, but I want to know if I would like to keep these two buttons, how should my code be modified so that the value of "goHome" can be changed before the form is submitted? After many attempts I am still getting $_POST["goHome"] = "".
Also, why is the form submitted before the value is actually changed when the code is placed before that?
Thanks!
It's old question But I thought If any one still looking for the answer , here it is
You can try jquery $('input[name="goHome"]').val('true');
or JS - document.getElementByName("goHome").value = "true";
This will work for sure.
While updating any value at the time of submitting for use name selector instead of ID, that will save you some time :)
When we try to change value of Hidden field at the time of submitting form it didn't update value because DOM has already detached the ID from the input parameter but name is still there because name is going to be passed in form.
If anyone find this useful and they do not have to work for lot hours for a simple solution :)
Happy Coding :)
Various ways to achieve this. Firstly though keep in mind that you are using type="submit" <input> inside a <form> , and that means that they will automatically submit the form regardless of an onclick event or not.
One as much as less intrusive (to your code) way is the following:
Take out the submit inputs from your form like this:
Example :
<form name = "addDataReal" id = "addDataReal" method = "POST" action = "whatever.php">
<!-- Other items -->
<input type = "hidden" name = "goHome" id = "goHome" value = "" />
</div>
</form>
<input type = "submit" name = "submitBtnF" id = "submitBtnF" class="shortText" style = "width: 120px;" value = "Submit + Home" onclick = "return getGoValue(true)"/>
<input type = "submit" name = "submitBtnR" id = "submitBtnT" class="shortText" style = "width: 120px;" value = "Submit + Next" onclick = "return getGoValue(false)"/>
Change your getGoValue() and checkNSub() functions like this :
function checkNSub() {
//form validation functions
//OK then return true
//Not then return false
var myForm = document.getElementById('addDataReal');
myForm.submit();
}
function getGoValue(goHome) {
if (goHome) {
document.getElementById("goHome").value = "true";
console.log(document.getElementById("goHome").value);
checkNSub();
} else {
document.getElementById("goHome").value = "false";
console.log(document.getElementById("goHome").value);
checkNSub();
}
return true;
}
Try it out.
P.S : A couple of console.logs so you can check out the value changing. Comment out checkNSub(); to see them in your console. Nevertheless keep in mind that you are posting a Form which means you are going to load a new page from the server , this new page will be agnostic regarding your "goHome" value. The "goHome" value exists only while you are on the same page. The moment your DOM is "recreated" you will lose it.
P.S.2 :
Your return true; inside the getGoValue(); is not needed in my
example. You can remove it.
the return in your onclick = "return getGoValue(true)" is also
not needed and you can remove it
P.S.3 :
This reply is focused on keeping most of your code intact. In reality now that you have your inputs outside the form there is no need for them to be of type="submit" you should change them to <button> with onClick events (or Listeners).

make a field mandatory using javascript

I am trying to make a select field mandatory on a web page. I know how to do it with help of JS and form attribute 'onsubmit' and returning the function. But the problem is that form code is already written and I dont know how to add attribute now. Let me know if I can append attribute dynamically from JS.
The other way I tried is to call the JS after page loaded. But this isnt making the field mandatory and form can be submitted.
Following is my code..
<!DOCTYPE html>
<html>
<head>
<script>
function f1()
{
var countryValue = document.getElementById('count ID').value;
if (countryValue == "")
{
alert("field value missing");
return false;
}
var stateValue = document.getElementById('state ID').value;
if (stateValue == "")
{
alert("state field value missing");
return false;
}
}
</script>
</head>
<body>
<form method = "post" action = "33.html">
Country: <input type="text" id="count ID">
state: <select id="state ID">
<option></option>
<option value="ap">ap</option>
<option value="bp">bp</option>
</select>
<br>
<input type = "submit">
</form>
<script>window.onload=f1</script>
</body>
</html>
Please help.
Have a look at this since you have messed up the IDs
Live Demo
window.onload=function() {
document.forms[0].onsubmit=function() { // first form on page
var countryValue = this.elements[0].value; // first field in form
if (countryValue == "") {
alert("Please enter a country");
return false;
}
var stateIdx = this.elements[1].selectedIndex; // second field
if (stateIdx < 1) { // your first option does not have a value
alert("Please select a state");
return false;
}
return true; // allow submission
}
}
PS: It is likely that POSTing to an html page will give you an error
To get the last button to do the submission
window.onload=function() {
var form = document.forms[0]; // first form
// last element in form:
form.elements[form.elements.length-1].onclick=function() {
...
...
...
this.form.submit(); // instead of return true
}
}
Once you've got a function to detect improper values (empty mandatory field or anything else, like a bad e-mail address for instance) you have a few different options :
disable the submit button
cancel the onclick event on the button
cancel the submit event on the form
disabling the submit button can be annoying for the user (it might flash on and off while the values are entered).
I had the same issue, but i made a extension. Using hook system to translate fields with "*", in the names, to validate like required field. This is a simple solution not intrusive where is not required addition of fields in the database, only by the use of sufix "*" in configuration of custom fields.
There is the code: https://github.com/voiski/bugzilla-required-field

javascript - why doesnt this work?

<form method="post" action="sendmail.php" name="Email_form">
Message ID <input type="text" name="message_id" /><br/><br/>
Aggressive conduct <input type="radio" name="conduct" value="aggressive contact" /><br/><br/>
Offensive conduct <input type="radio" name="conduct" value="offensive conduct" /><br/><br/>
Rasical conduct <input type="radio" name="conduct" value="Rasical conduct" /><br/><br/>
Intimidating conduct <input type="radio" name="conduct" value="intimidating conduct" /><br/><br/>
<input type="submit" name="submit" value="Send Mail" onclick=validate() />
</form>
window.onload = init;
function init()
{
document.forms["Email_form"].onsubmit = function()
{
validate();
return false;
};
}
function validate()
{
var form = document.forms["Email_form"]; //Try avoiding space in form name.
if(form.elements["message_id"].value == "") { //No value in the "message_id"
box
{
alert("Enter Message Id");
//Alert is not a very good idea.
//You may want to add a span per element for the error message
//An div/span at the form level to populate the error message is also ok
//Populate this div or span with the error message
//document.getElementById("errorDivId").innerHTML = "No message id";
return false; //There is an error. Don't proceed with form submission.
}
}
}
</script>
Am i missing something or am i just being stupid?
edit***
sorry i should add! the problem is that i want the javascript to stop users going to 'sendmail.php' if they have not entered a message id and clicked a radio button... at the moment this does not do this and sends blank emails if nothing is inputted
You are using
validate();
return false;
...which means that the submit event handler always returns false, and always fails to submit. You need to use this instead:
return validate();
Also, where you use document.forms["Email form"] the space should be an underscore.
Here's a completely rewritten example that uses modern, standards-compliant, organised code, and works:
http://jsbin.com/eqozah/3
Note that a successful submission of the form will take you to 'sendmail.php', which doesn't actually exist on the jsbin.com server, and you'll get an error, but you know what I mean.
Here is an updated version that dumbs down the methods used so that it works with Internet Explorer, as well as includes radio button validation:
http://jsbin.com/eqozah/5
You forgot the underscore when identifying the form:
document.forms["Email_form"].onsubmit = ...
EDIT:
document.forms["Email_form"].onsubmit = function() {
return validate();
};
function validate() {
var form = document.forms["Email_form"];
if (form.elements["message_id"].value == "") {
alert("Enter Message Id");
return false;
}
var conduct = form.elements['conduct']; //Grab radio buttons
var conductValue; //Store the selected value
for (var i = 0; i<conduct.length; i++) { //Loop through the list and find selected value
if(conduct[i].checked) { conductValue = conduct[i].value } //Store it
}
if (conductValue == undefined) { //Check to make sure we have a value, otherwise fail and alert the user
alert("Enter Conduct");
return false;
}
return true;
}
return the value of validate. Validate should return true if your validation succeeds, and false otherwise. If the onsubmit function returns false, the page won't change.
EDIT: Added code to check the radio button. You should consider using a javascript framework to make your life easier. Also, you should remove the onclick attribute from your submit input button as validation should be handled in the submit even, not the button's click
Most obvious error, your form has name attribute 'Email_form', but in your Javascript you reference document.forms["Email form"]. The ironic thing is, you even have a comment in there not to use spaces in your form names :)

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