Getting error [object HTMLCollection] - javascript

I am having a problem in making a simple test in javascript. This is a quick example. Each question's div id is incremented in the html code.
HTML
<form action="#">
<div id="q1">
<label>Q. ABCD</label>
<label><input type="radio" name="radio1" value="1">A</label>
<label><input type="radio" name="radio1" value="2">B</label>
<label><input type="radio" name="radio1" value="3">C</label>
<label><input type="radio" name="radio1" value="4">D</label>
</div>
....
....
<input type="button" value="Click to Submit" onClick="result();">
</form>
JS (say for 10 questions)
function result() {
var answer = new Array();
for(var i=1; i<11 ; i++) {
if(document.getElementById("q" + i).getElementsByTagName("input") != undefined) {
answer[i] = document.getElementById("q" + i).getElementsByTagName("input");
}
else {
answer[i] = 0;
}
}
console.log(answer);
}
I am getting an error [object HTMLCollection] every time I submit the code. How should I do this so that I can get the value of each answer given inside the array and if someone doesn't answer any question, the array must get 0 value at its place instead of undefined. I need a pure JS and HTML solution.

Try this one
function result() {
var answer = new Array();
// there is no answer 0
answer[0] = 'unused';
for(var i=1; i<11 ; i++) {
// check if the id exists first
var container = document.getElementById("q" + i);
if(container) {
// get the selected radio checkbox
var input = container.querySelector("input:checked");
// if there's one selected, save it's value
if(input) {
answer[i] = input.value;
}
else {
answer[i] = 0;
}
}
}
console.log(answer);
}
a working fiddle - http://jsfiddle.net/dtpLjru1/

In your code, you are trying to store the HTML collection by using getElementByTagName(). This method will return all the Tags with the name of "input", so total of 4 tags as per the code above.
Instead of that, you can modify your code like below.
Assuming, you want to store "1" in case radio button is checked. else 0
function result() {
var answer = new Array();
for (var i = 1; i <= 4 ; i++) {
if (document.getElementById("q" + i).getElementsByTagName("input") != undefined) {
answer[i] = document.getElementById("q" + i).checked ? 1 : 0;
}
else {
answer[i] = 0;
}
}
console.log(answer);
}

Have not tested the code, How about we do this ?
function result() {
var answer = new Array();
for(i=1; i<11 ; i++) {
if(document.getElementById("q" + i).getElementsByTagName("input") != undefined) {
document.write( document.getElementById("q" + i).getElementsByTagName("input") );
}
else {
document.write(0);
}
}
}

Related

What is the best way to combine and evaluate user input through javascript?

(I'm very new to this, please bear with me)
I'm making several modules that require user input and I want to somehow combine the input to produce an output. I was thinking of assigning each option a value and adding them together and creating an if/else statement to determine the output...
For example, if the user selects three options with values 1, 2, 3 and the statement says that any combined value greater than 5 will get a result of "Good", then the selected options will get a response of "Good" because when combined, they equal 6 (which is >5).
Does anyone know a better way, and/or can you direct me to some reference sites that might have what I'm looking for?
Thank you so much!! Any help is appreciated!!
Are you looking for something like this?
<form id="module1">
<input name="option1" type="checkbox" value="Orange"> Orange
<input name="option2" type="checkbox" value="Banana"> Banana
<input name="option3" type="checkbox" value="Apple"> Apple
<input name="option4" type="checkbox" value="Mango"> Mango
<input name="option5" type="checkbox" value="Pineapple"> Pineapple
</form>
<button id="evaluate" type="button">Evaluate</button>
<h4 id="result"></h4>
<h5 id="values"></h5>
<script type="text/javascript">
$(document).ready(function () {
var scoreConstants = {
'Mango': 100,
'Banana': 100,
'Pineapple': 200,
'Orange': 50,
'Apple': 250
};
var evalScore = function (selectedValues) {
var totalScore = 0;
$.each(selectedValues, function (k, v) {
totalScore += scoreConstants[v];
});
return totalScore;
}
var getScoreLabel = function (score) {
var scoreValue = 'Score: ';
if (score < 200) {
scoreValue += 'Average';
} else if (score >= 200 && score < 500) {
scoreValue += 'Good';
} else if (score >= 500) {
scoreValue += 'Excellent!';
}
return scoreValue;
}
$('body').on('click', '#evaluate', function (e) {
var $selectedValues = $('#module1').find('input:checked');
var selectedValues = [];
$selectedValues.each(function (k, v) {
var $selected = $(v);
selectedValues.push($selected.val());
});
var score = evalScore(selectedValues);
var scoreLabel = getScoreLabel(score);
var valueString = 'Selected: ';
if (selectedValues.length > 0) {
$.each(selectedValues, function (k, v) {
if (k === (selectedValues.length - 1)) {
valueString += v;
} else {
valueString += v + ', '
}
});
} else {
valueString += 'None';
}
var $result = $('#result');
$result.html(scoreLabel);
var $displayValues = $('#values');
$displayValues.html(valueString);
});
});
</script>
See the code working here:
https://jsfiddle.net/0x2L0dek/1
I think you are looking for this.
To see the result, check your console.
<input type="checkbox" class="chk" value=1>1</input><br>
<input type="checkbox" value=2 class="chk">2</input><br>
<input type="checkbox" value=3 class="chk">3</input><br>
<input type="checkbox" value=4 class="chk">4</input><br>
<button id="button1" onclick="checkSum()">Submit</button>
<script>
function checkSum(){
var chk = document.getElementsByClassName('chk');
sum = 0;
for(var i=0; chk[i]; ++i){
if(chk[i].checked){
sum = sum + parseInt(chk[i].value);
}
}
console.log(sum);
if(sum > 5){
console.log("Good");
}
}
</script>

Radio Button list selected items value in javascript

I am using following code to get the selected elements value in radio button list.
function SelectRadioButton()
{
var radiobutton = document.getElementsByName('<%=RadioButtonList1.ClientID %>');
alert(radiobutton.length);
for(var x = 0; x < radiobutton.length; x++)
{
if(radiobutton[x].checked)
{
alert('selected is ' + radiobutton[x].id);
}
}
}
Following is the HTML markup
<table id="ctl00_ContentPlaceHolder1_idControl_RadioButtonList1" class="chk" onclick="javascript:SelectRadioButton(this, ctl00_ContentPlaceHolder1_idControl_RadioButtonList1)" border="0">
<tr>
<td><input id="ctl00_ContentPlaceHolder1_idControl_RadioButtonList1_0" type="radio" name="ctl00$ContentPlaceHolder1$idControl$RadioButtonList1" value="1" checked="checked" /><label for="ctl00_ContentPlaceHolder1_idControl_RadioButtonList1_0">List</label></td><td><input id="ctl00_ContentPlaceHolder1_idControl_RadioButtonList1_1" type="radio" name="ctl00$ContentPlaceHolder1$idControl$RadioButtonList1" value="2" /><label for="ctl00_ContentPlaceHolder1_idControl_RadioButtonList1_1">Assignment</label>
But I am getting length 0 in alert(radiobutton.length); statement.
Why is this happening. any thing that I am missing?
You can use jquery to do this.
alert($(".chk").find("input:checked").length); // chk is your css class name applied to Checkbox List element.
You can get specific element by using this
alert($(".chk").find("input:checked")[0]);
RadioButtonList1 will be converted to radio buttons with ids having RadioButtonList1, You can iterate through DOM and look for matched ids and put them in some array or directly perform what you want to them.
radiobutton = [];
for(i=0;i<document.forms[0].length;i++)
{
e=document.forms[0].elements[i];
if (e.id.indexOf("RadioButtonList1") != -1 )
{
radiobutton.push(e);
}
}
Here's how you do it with javascript only, if you don't want to use getElementById
Code | JSFiddle
function SelectRadioButton(){
var radiolist = getElementsByClass("table", "chk")[0],
radios = radiolist.getElementsByTagName("input");
for(var i = 0; i < radios.length; i++){
if(radios[i].checked){
alert('Selected radiobutton is ' + radios[i].id);
}
}
}
function getElementsByClass(tag, name){
var elements = document.getElementsByTagName(tag);
var ret = [];
for(var i = 0; i < elements.length; i++){
if(elements[i].className.indexOf(name) !== -1){
ret.push(elements[i]);
}
}
return ret;
}

Javascript Toggle Check All Nested Array Names

I'm having a problem trying to create a Javascript function that checks all the checkboxes in a form.
An example of the checkboxes on my form look like
<b>A:</b> <input type="checkbox" name="multipleForms[201][A]"><br>
<b>B:</b> <input type="checkbox" name="multipleForms[201][B]"><br>
<b>C:</b> <input type="checkbox" name="multipleForms[201][C]"><br>
<b>D:</b> <input type="checkbox" name="multipleForms[201][D]"><br>
<b>A:</b> <input type="checkbox" name="multipleForms[500][A]"><br>
<b>B:</b> <input type="checkbox" name="multipleForms[500][B]"><br>
<b>C:</b> <input type="checkbox" name="multipleForms[500][C]"><br>
And what I want to do is be able to pass a number such as 201 and 500 into a Javascript function and have all checkboxes with the first array index as that integer be checked.
So, checkAll(201) would have the first 4 checkboxes checked and checkAll(500) would have the other 3 checkboxes checked.
I would rather not change the names of my checkboxes if that is possible as the stringed indexes are really important for my PHP code.
Thanks in advance.
Also, I would rather have non-jQuery code.
Something like that ? : http://jsfiddle.net/RZPNG/6/
var checkboxes = document.getElementsByTagName('input');
function check(num) {
for (var i = 0; i < checkboxes.length; i++) {
if (parseInt(checkboxes[i].name.split('[')[1]) === num) {
checkboxes[i].checked = 'checked';
}
}
}
check(201);​
Something like the following should do:
function checkBoxes(form, s) {
var input, inputs = form.getElementsByTagName('input');
var re = new RegExp(s);
for (var i=0, iLen=inputs.length; i<iLen; i++) {
input = inputs[i];
if (input.type == 'checkbox' && re.test(input.name)) {
input.checked = true;
} else {
input.checked = false;
}
}
}
You could also use querySelectorAll, but support isn't that common yet:
function checkBoxes(s) {
var els = document.querySelectorAll('input[name*="' + s + '"]');
for (var i=0, iLen=els.length; i<iLen; i++) {
els[i].checked = true;
}
}

Shortening JavaScript Function

I must admit, I don't know much about JavaScript that is why my question might sound little bit silly.
But what I'm trying to do is grab values from selected by name radio groups.
It looks like this
function calc() {
var op1 = document.getElementsByName('form[radio1]');
var op2 = document.getElementsByName('form[radio2]');
var op3 = document.getElementsByName('form[radio3]');
var result = document.getElementById('result');
result.value = 0;
result.value = parseInt(result.value);
for (i = 0; i < op1.length; i++) {
if (op1[i].checked) result.value = parseInt(result.value) + parseInt(op1[i].value);
}
for (i = 0; i < op2.length; i++) {
if (op2.options[i].selected) result.value = parseInt(result.value) + parseInt(op2[i].value);
}
for (i = 0; i < op3.length; i++) {
if (op3.options[i].selected) result.value = parseInt(result.value) + parseInt(op3[i].value);
}
return false;
}
And this is my form. Im using rs form for joomla.
<form action="index.php" enctype="multipart/form-data" id="userForm" method="post">
<input name="form[radio1]" value="25" id="radio20" type="radio">
<label for="radio20">Description1</label>
<input name="form[radio1]" value="35" id="radio21" type="radio">
<label for="radio21">Description2</label>
<input name="form[radio2]" value="20" id="radio20" type="radio">
<label for="radio20">Description1</label>
<input name="form[radio2]" value="30" id="radio21" type="radio">
<label for="radio21">Description2</label>
<input type="hidden" value="0" id="result" name="form[result]">
<input type="submit" class="rsform-submit-button" onclick="calc()" id="submit" name="form[submit]" value="submit">
And everything would be OK, as the function is working. the only trouble is that I have about 80 radiograms.
Is there a way to shorten it?
Use arrays of objects (like all the radio buttons, for instance) and iterate over them. Start like this:
var opts = [],
numOpts = 80;
for (var i=0; i<numOpts, i++)
{
opts.push(document.getElementsByName('form[radio' + i + ']'));
}
Edit: let's have a go at the full function. The only thing I'm not 100% sure about is whether you mean to use opX[i].checked or opX.options[i].selected (since your code does different things for op1 and op2/3). Shouldn't be too hard to extrapolate if I've guessed wrong, though.
function calc()
{
var opts = [],
numOpts = 80,
value = 0,
result = document.getElementById('result'),
i, j, opt;
for (i=0; i<numOpts; i++)
{
opts.push(document.getElementsByName('form[radio' + i + ']'));
}
numOpts = opts.length;
for (i=0; i<numOpts; i++)
{
opt = opts[i];
for (j=0; j<opt.length; j++)
{
// or did you mean:
// if (opt.options[j].selected) ?
if (opt[j].checked)
{
value = value + parseInt(opt[j].value, 10);
}
}
}
result.value = value;
return false;
}
jQuery is a great library that's like using JavaScript on steroids. It is well worth learning and there are plenty of examples out in the wild.
You can write complex "selectors" quite like this:
$('input[name=form[radio1]]').attr('checked').each(function() {
result.value = $(this).attr('value')
})
(I'm not sure if it will accept a name like "form[radio1]" as valid, but give it a try.

Fast way to validate if all checkboxes are un-selected?

Is there a quick way or function that would tell me true/false if all check boxes are deselected? Without going through array? (with JS and HTML)
All my check boxes have the same name...
<form action="/cgi-bin/Lib.exe" method=POST name="checks" ID="Form2">
<input type=checkbox name="us" value="Joe" ID="Checkbox1">
<input type=checkbox name="us" value="Dan" ID="Checkbox2">
<input type=checkbox name="us" value="Sal" ID="Checkbox3">
</form>
jQuery would be a mass of unneeded bloat for a task this trivial. Consider using it if you are running it for other purposes, but all you need is something like this:
function AreAnyCheckboxesChecked () {
var checkboxes = document.forms.Form2.elements.us;
for (var i = 0; i < checkboxes.length; i++) {
if (checkboxes[i].checked) {
return true;
}
}
return false;
}
You have to loop through them. Even a library like jQuery will loop through them, just hide it from you.
var form = document.getElementById('Form2');
var inputs = form.getElementsByTagName('input');
var is_checked = false;
for(var x = 0; x < inputs.length; x++) {
if(inputs[x].type == 'checkbox' && inputs[x].name == 'us') {
is_checked = inputs[x].checked;
if(is_checked) break;
}
}
// is_checked will be boolean 'true' if any are checked at this point.
JavaScript:
var allischecked = (function(){
var o = document.getElementById("Form2").getElementsByTagName("input");
for(var i=0,l=o.length;i<l;i++){
o[i].type === "checkbox" && o[i].name === "us" && o[i].checked || return false;
}
return true;
})();
With jQuery:
var allischecked = ($("#Form2 input:checkbox:not(checked)").length === 0);
In summary, this snipped will return true if all are NOT checked. It bails out as soon as a checked one is found.
var a = document.getElementsByName("us");
for(var i=0; i<a.length; i++)
if(a[i].checked)
return false;
return true;
(did not test, but conceptually it is valid)
What do you mean by
Without going through array
?
You could just do
function check() {
var anyChecked = false;
var form = document.getElementById('Form2');
var checkboxes = form.getElementsByTagName('input');
for(var i=0; i < checkboxes.length; i++) {
if (checkboxes[i].checked) {
anyChecked = true;
break;
}
}
alert("Checkboxes checked? " + anyChecked);
}
Working Demo
If you have a large amount of checkboxes that you don't want to loop through to test it might be more efficient to use this approach.
var checked = 0;
$("input[type=checkbox]").live("click", function() {
if($(this).attr("checked")) checked++;
else checked--;
}
Then you would be able to test like this.
if(checked === 0) {
doSomething();
}
The proper solution with jQuery attribute checked:
$checkboxes = $('#Form2 input:checkbox');
$checkboxes.on('click', checkboxes);
function checkboxes() {
var allChecked = $checkboxes.not(':checked').length == 0;
console.log(allChecked);
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>
<form action="/cgi-bin/Lib.exe" method=POST name="checks" ID="Form2">
<input type=checkbox name="us1" value="Joe" ID="Checkbox1"><label>Joe</>
<input type=checkbox name="us2" value="Dan" ID="Checkbox2"><label>Dan</>
<input type=checkbox name="us3" value="Sal" ID="Checkbox3"><label>Sal</>
</form>
Even easier without loop
const toggleCheckboxes = checkbox => {
if(checkbox.checked){
return true
}else{
if(document.querySelectorAll(':checked').length === 0){
// All are unchecked
return false
}
}
}

Categories

Resources