Highlight empty select box after alert - javascript

I have a site using input:text, select and select multiple elements that generate a text output on button click.
Having searched SO, I found examples of validation code that will alert the user when a select field returns an empty value-
// alert if a select box selection is not made
var selectEls = document.querySelectorAll('select'),
numSelects = selectEls.length;
for(var x=0;x<numSelects;x++) {
if (selectEls[x].value === '') {
alert('One or more required fields does not have a choice selected... please check your form');
return false;
$(this).addClass("highlight");
}
At the end, I tried to add a condition after the alert is dismissed, such that the offending select box will be highlighted by adding the 'highlight' class - but this doesn't do anything. My .highlight css is {border: 1px red solid;}
Any help here?
UPDATED WITH ANSWER - Thanks #Adam Rackis
This code works perfectly. I added a line to remove any added '.highlight' class for selects that did not cause an error after fixing
// alert if a select box selection is not made
var selectEls = document.querySelectorAll('select'),
numSelects = selectEls.length;
$('select').removeClass("highlight");//added this to clear formatting when fixed after alert
var anyInvalid = false;
for(var x=0;x<numSelects;x++) {
if (selectEls[x].value === '') {
$(selectEls[x]).addClass("highlight");
anyInvalid = true;
}}
if (anyInvalid) {
alert('One or more required fields does not have a choice selected... please check your form');
return false;
}

You were close. In your loop, this does not refer to each select that you're checking.
Also, you're returning false prior to the highlight class being added. You'll probably want to keep track of whether any select's are invalid, and return false at the very end after you're done with all validation.
Finally, consider moving your alert to the very bottom, so your user won't see multiple alerts.
var anyInvalid = false;
for(var x=0;x<numSelects;x++) {
if (selectEls[x].value === '') {
$(selectEls[x]).addClass("highlight");
anyInvalid = true;
}
}
if (anyInvalid) {
alert('One or more required fields does not have a choice selected... please check your form');
return false;
}
Also, since you're already using jQuery, why not take advantage of its features a bit more:
$('select').each(function(i, sel){
if (sel.value === '') {
$(el).addClass("highlight");
anyInvalid = true;
}
});
if (anyInvalid) {
alert('One or more required fields does not have a choice selected... please check your form');
return false;
}

Related

jQuery - Validation

I'm having an issue with my validation process. I'm not using a standard "submit" button, rather I have <span class="button" id="print">Print</span> and jQuery listens for a click. This is the validation code I have when that "button" is clicked:
var validation = "";
function validate() {
$("#servDetails").find("input").each(function () {
if ($(this).prop("required") && $(this).val() == "") {
validation = false;
}
else {
validation = true;
}
});
$("#checklist").find("input[required]").each(function () {
if ($(this).prop("required") && $(this).val() == "") {
validation = false;
}
else {
validation = true;
}
});
}
$("#print").on("click", function() {
validate();
if (validation == false) {
alert("Please fill out all required inputs!");
return false;
}
else {
window.print();
}
});
If I click the button without filling anything out (all items blank), I get my alert as expected.
If I fill out all of the required elements, it pulls up the print dialouge as expected.
However, if I leave some of the boxes blank while others are correctly filled, it still goes to print instead of giving me the alert like I need. Any thoughts?
The code have to be rewritten, or better replace it with any validation plug-in.
But in your case, I suppose, you just forgot to return, in case you found some not filled field. So if you have any filled input it override your validation variable.
The simplest solution is to remove
else {validation = true;} code blocks, and add
validation = true;
at the beggining of the function.

How to hide the next button on qualtrics until a text field is filled in with text?

I have a survey with two questions on the page (one that is multiple choice) and one that is a text entry question.
I want to hide the next button until the text entry question has been filled out but I've only been able to hide the next button indefinitely and it seems to not reappear after the text field has been filled in.
Qualtrics.SurveyEngine.addOnload(function()
{
this.hideNextButton();
(function() {
$('form > input').keyup(function() {
var empty = false;
$('form > input').each(function() {
if ($(this).val() == '') {
empty = true;
}
});
if (empty) {hideNextButton ()} else {showNextButton ()}
});
});
});
You have some syntax errors. It looks like you are trying to use jQuery instead of Prototypejs. Besides that, you need to restrict your input element search to the question and there is only one input field so you only need one function. Try this (edited to defer initial next button hide):
Qualtrics.SurveyEngine.addOnload(function() {
function hideEl(element) {
element.hide();
}
var nb = $('NextButton');
hideEl.defer(nb);
$(this.questionId).down('.InputText').on('keyup', function(event) {
if(this.value.length == 0) nb.hide();
else nb.show();
});
});

Can not validate properly the radio button using JavaScript/jQuery

I cannot check the radio button select in my validation using JavaScript/jQuery. I am generating some multiple textarea, radio button and drop down list dynamically. My requirement is I will fill all field and check the validation. But it's not happening properly.
Here is my code:
function validate(){
var x =document.getElementById('ques').value;
console.log('value',x);
for(var i=0;i<x;i++){
var tid="questions"+ i;
var rid='answer_type'+i;
var sid="nscale"+i;
var scaleid='#scaleid'+i;
if(document.getElementById("questions"+ i)){
if(document.getElementById(tid).value==''){
alert('Please enter the question');
return false;
}else if($('input[id=answer_type' + i + ']').is(':checked')==false){
alert('Please check the answer type');
return false;
}else if($(scaleid).css('display') == 'block'){
if(document.getElementById(sid).value==''){
alert('Please select the scale');
return false;
}
}else{
}
}
}
}
My complete code is here plunkr. My problem is when user has selected all radio button and also click on validate button still its displaying the alert message as Please check the answer type. My requirement is I will check all field and drop down list whether these are blank or not in validation case.
Try and make the id of radio button in the addQuestionField() function as id="answer_type'+i+'" instead of id="answer_type0".

JQuery MultiPage form.. validation on each step

I have a form which is split up into sections using pagination on each tag. (See Fiddle)
I however have required fields in each section, I'd like to validate it so that fields with the "required" attribute must not be blank before the user moves on to the next section.
http://jsfiddle.net/Azxjt/
I've tried to following but don't think I'm on the right tracks:
$(this).closest("article > :input").each(function() {
if($(this).val == null) {
con = 0;
}
});
if ( con == 0 ) {
alert("All fields must be filled in");
}
else {
}
Your help is appreciated :)
Text input will return a black value if no response has been entered. Try the following
In jQuery, the value is returned by val()
$(this).val() == ""
You could possibly enhance your jQuery selector to test only those input elements with a corresponding required label.
Use each function.
var isEmpty;
$("input").each(function() {
var element = $(this);
if (element.val() == "") {
isEmpty= true;
}
});

How to test if users has made any changes to a form if they haven't saved it

Basically the same functionality as stackoverflow when posting a question, if you start writing a post then try to reload the page. You get a javascript alert box warning message.
I understand how to check if the form has been changed, although how do I do the next step.
I.E: How to I check this when leaving the page, on here you get "This page is asking you to confirm that you want to leave - data you have entered may not be saved."?
EDIT: found correct answer here to another question https://stackoverflow.com/a/2366024/560287
I'm very sure that if you search, 'jQuery detect form change plugin', you will find something much more usable than this semi-pseudo code i'm about to write:
formChanged = function(form) {
form.find('input[type="text"], textarea').each(function(elem) {
if (elem.defaultValue != elem.value) {
return true;
}
});
// repeat for checkbox/radio: .defaultChecked
// repeat for ddl/listbox: .defaultSelected
return false;
}
usage:
if (formChanged($('form')) { // do something }
Note that this is to detect changes against the original rendered value. For instance, if a textbox has a value = "x", and the user changes it to "y", then changes it back to "x"; this will detect it as NO change.
If you do not care about this scenario, you can just do this:
window.formChanged = false;
$(':input').change(function() {
window.formChanged = true;
});
Then you can just check that value.
Yes, it is JavaScript as HTML is just a markup language.
Yes, jQuery can be used for this. It's preferable over vanilla JavaScript as it makes things easier, although it does add some overhead.
There are a number of ways to check if any of a form's controls have changed.
To check for changes from the default, most can be checked against the defaultValue property. For radio buttons, you should always have one checked by default, so check if it's still selected or not. Similarly for selects, set the selected attribute for the default option and see if it's still selected, and so on.
Alternatively, if all your form controls have an ID or unique name, you can collect all their values onload and then check their values when the form is submitted.
Another method is to listen for change events on each form control, but that is a bit over the top.
Here's a POJS version that takes the same approach as rkw's answer:
/*
Check if any control in a form has changed from its default value.
Checks against the default value for inputs and textareas,
defaultChecked for radio buttons and checkboxes, and
default selected for select (option) elements.
*/
function formChanged(form) {
var control, controls = form.elements;
var tagName, type;
for (var i=0, iLen=controls.length; i<iLen; i++) {
control = controls[i];
tagName = control.tagName.toLowerCase();
type = control.type;
// textarea
if (tagName == 'textarea') {
if (control.value != control.defaultValue) {
return true;
}
// input
} else if (tagName == 'input') {
// text
if (type == 'text') {
if (control.value != control.defaultValue) {
return true;
}
// radio and checkbox
} else if (type == 'radio' || type == 'checkbox') {
if (control.checked != control.defaultChecked) {
return true;
}
}
// select multiple and single
} else if (tagName == 'select') {
var option, options = control.options;
for (var j=0, jLen=options.length; j<jLen; j++) {
option = options[j];
if (option.selected != option.defaultSelected) {
return true;
}
}
}
}
// Not really needed, but some like the return value to
// be a consistent Type
return false;
}
Note that you need to be careful with select elements. For a single select, you should always set one option to selected, as if there is no default selected, some browsers will make the first option selected and others wont.

Categories