Adding options to a select box dynamically - javascript

I am trying to add options to select element using javascript dynamically for a university assignment.
We are creating a class booking system for a gym so users can book into a class. I wanted to use drop down boxes, so you select the class, then the time using the next drop down box, so it has to change depending on the class selected. Finally, the user would select the personal trainer in the last box, once again created depending on what timeslot is selected.
This is what I have so far (javascript side):
<script type="text/javascript">
function getTimes()
{
var index=document.getElementById("classes").selectedIndex;
var x=document.getElementById("schedule");
if(index==0)
{
document.getElementById("schedule").value=" ";
}
else if(index==1)
{
var option=document.createElement("option");
option.text="Monday 8:00pm";
try
{
// for IE earlier than version 8- from w3 schools
x.add(option,x.options[null]);
}
catch (e)
{
x.add(option,null);
}
}
}
and html:
<div>
<span class="label">Class:</span>
<select class="dropdown" id="classes" name="classes" onChange="getTimes();">
<option value="none"> </option>
<option value="pilates">Pilates</option>
<option value="crossfit">Cross Fit</option>
</select>
</div>
<div>
<span class="label">Time:</span>
<select class="dropdown" id="schedule"></select>
</div>
<div>
<span class="label">Trainer:</span>
<select class="dropdown" id="trainer"></select>
</div>
To the code seems like it should work, but for whatever reason when I select the first class, in this case "Pilates" the "Time" drop down box is still blank.
Can anyone tell me where I am going wrong?

The error is in the first line of the function
function getTimes();
^------ You have a semi colon here
which is not supposed to be there
Also is a better idea to cache your selectors if you are referencing the same element again.
Bind the events using Javascript instead of binding them inline.
// Store you selectors so that you can use later
// This will improve your performance
var classDropdown = document.getElementById("classes"),
scheduleDropdown = document.getElementById("schedule");
// Abbd events using javascript
classDropdown.addEventListener('change', getTimes);
function getTimes() {
var index = classDropdown.selectedIndex;
if (index == 0) {
scheduleDropdown.value = " ";
} else if(index == 1) {
var option = document.createElement("option");
option.text = "Monday 8:00pm";
try {
// for IE earlier than version 8- from w3 schools
scheduleDropdown.add(option, x.options[null]);
} catch (e) {
scheduleDropdown.add(option, null);
}
}
}
Check Demo

Related

Select a drop-down value using javascript (Bookly WP Plugin)

I'm trying to select a drop-down value using js. In my case, I need to select "DRAW PORTRAIT" drop-down option after the plugin loads.
I tried two methods but I'm not getting anywhere. This is a part of the frontend found in Bookly WordPress plugin. I added an id id="category" to the dropdown so that I can select a value.
HTML:
<div class="bookly-js-chain-item bookly-table bookly-box" style="display: table;">
<div class="bookly-form-group">
<label>Service Type</label>
<div>
<select id="categorydraw" class="bookly-select-mobile bookly-js-select-category">
<option value="">Select category</option>
<option value="6">DRAW PORTRAIT</option>
<option value="7">DRAW DUMMY FIGURE</option>
<option value="8">DESIGN WAX SCULPTURE</option></select>
</div>
</div>
</div>
Method 01
document.getElementById("categorydraw").value = "DRAW PORTRAIT";
Method 02
var objSelect = document.getElementById("categorydraw");
setSelectedValue(objSelect, "DRAW PORTRAIT");
function setSelectedValue(selectObj, valueToSet) {
for (var i = 0; i < selectObj.options.length; i++) {
if (selectObj.options[i].text== valueToSet) {
selectObj.options[i].selected = true;
return;
}
}
}
Please see the full code where the js doesn't work: https://jsfiddle.net/3z5hcv62/
I would really appreciate if someone can correct my cranky code. Thanks in advance!
One line of jQuery will allow you to select the item necessary:
$('#categorydraw option[value="7"').prop("selected", true);
https://jsfiddle.net/fLc1p5mq/
Edit: In order to activate on a WordPress page load, use:
jQuery( document ).ready(function() {
jQuery('#categorydraw option[value="7"').prop("selected", true);
});
First, i want to make sure. Do you want to select the value of the dropdown or set the value to the dropdown?. Maybe this will help your problem.
HTML
<!-- I set the "categories" id to the dropdown -->
<select class="bookly-select-mobile bookly-js-select-category" id="categories">
<option value="">Select category</option>
<option value="1">Cosmetic Dentistry</option>
<option value="2">Invisalign</option>
<option value="3">Orthodontics</option>
<option value="4">Dentures</option>
</select>
<p>
Selected value: <strong id="selected"></strong>
</p>
JavaScript
var dropdown = document.getElementById('categories');
var datas = [];
var select = 3;
/* Get value with text from dropdown */
for(var i=0;i<dropdown.options.length;i++) {
datas.push({
id: dropdown.options[i].value,
text: dropdown.options[i].text,
});
}
/* For set the value */
dropdown.value = select; // after page loaded,, default value will selected is "Orthodontics"
/* For select current value with the text */
var dataSelected = datas[select];
document.getElementById('selected').innerHTML = "ID: "+dataSelected.id+", TEXT: "+dataSelected.text;
The result will show like this https://jsfiddle.net/65jnzLko/1/
You can improve that code. Like selecting datas by id of the dropdown value.
Or if you just want to set the value for your dropdown, you can do this
// using pure js
document.getElementById('yourdropdown').value = 3 // or other values
// using jquery
$("#yourdropdown").val(5) // 5 can replace with other values

Why is the code not reassigning the class to the id'ed tag but breaking instead?

Could someone please give me a hand with the below issue?
I have got a simple drop down menu with 3 options and would like to remove a "hidden" class (simple CSS with display: none) allocated by default to a div when option 3 (with a value of RU) is chosen but RE-ADD / leave the class when option 1 or 2 are chosen (again).
The HTML for the hidden div is like this :
<div class="hidden" id="cityRestrictions">
<label for="cityQuery">Please select the city you were calling from: </label>
<select id="cityQuery">
<option value="Moscow"> Moscow </option>
<option value="StPetersburg"> Saint Petersburg </option>
<option value="Other"> Other </option>
</select>
</div>
My javascript is as follows:
dialInLocation.addEventListener("change", function() {
let location = document.getElementById('dialInLocation');
if(location.value == "RU") {
removeActivityItem();
}
});
function removeActivityItem() {
cityRestrictions = cityRestrictions.removeAttribute("class");
}
this works fine. If i choose the option with the value RU in the drop down, the class hidden is removed from the div and the content is displayed.
However if i add an
if(location.value == "RU") {
removeActivityItem();
} else {
addActivityItem();
}
with addActivityItem defined as :
function addActivityItem() {
cityRestrictions = cityRestrictions.setAttribute("class","hidden");
}
Then my code is completely broken.
First of all, if cityRestrictions is an element then you don't need to type cityRestrictions = cityRestrictions.setAttribute("class","hidden") because you can just type cityRestrictions.setAttribute("class","hidden");
Second of all, instead of adding the class and taking it away, I recommend changing the style by using cityRestrictions.style.display = "none"; and cityRestrictions.style.display = "block";

Select Download File from One of Two Select Boxes with One Button - JavaScript

I have two select boxes like so:
<select id="one">
<option value="default">Select File</option>
<option value="path/to/file1">File One</option>
<option value="path/to/file2">File Two</option>
<option value="path/to/file3">File Three</option>
</select>
<select id="two">
<option value="default">Select File</option>
<option value="path/to/file4">File Four</option>
<option value="path/to/file5">File Five</option>
<option value="path/to/file6">File Six</option>
</select>
<p class="button_image">
<a onclick="download(document.getElementById("one").value)"></a>
</p>
Here is my download function:
function download(file) {
if (file == 'default') return;
window.location = 'http://www.mysite.com/download/' + file;
}
This works fine for one select box, but I can't seem to figure out how to use the same button image. Oh yah, the p.class=button_image has background image that is a button with hover effects.
The reason I want these select boxes to be separate is because they each represent a group of files, eg, 32-bit versus 64-bit. So they cannot be combined, because it won't flow with the page design.
I've tried some if/else blocks in PHP using the getElementById but I'm getting stuck. This is what I tried and it seems to only partially work:
<?php
if ('document.getElementById(\"one\")' == 'one') {
echo "<a onclick='download(document.getElementById(\"one\").value)'></a>";
}
else if ('document.getElementById(\"two\")' == 'two') {
echo "<a onclick='download(document.getElementById(\"one\").value)'></a>";
}
?>
I should note that I don't necessarily need to use PHP in this case to solve this problem. It was just an option I tried because I'm using PHP for the server-side programming. I could be happy with any number of options, so long as they work.
Thanks.
** EDIT **
This design might be flawed. But the intention is that either a file from box one is downloaded OR a file from box two is downloaded. If one selection is made, then the other should be rest to default and vice versa. This is what I'm working on now.
** EDIT **
I ended up goign with Dawson Loudon's answer for one part and I created another function based on Barmar's comment that looks like this:
// resets other select box when selected
function reset_index(id) {
document.getElementById(id).selectedIndex = 'default';
}
An A element as a button doesn't seem appropriate, just use an img.
Anyhow, a function to use the first select with a selected option other than the first can be something like:
function getPath() {
var select;
var args = arguments;
for (var i=0, iLen=args.length; i<iLen; i++) {
select = document.getElementById(arg[i]);
if (select && select.selectedIndex > 0) {
window.location = 'http://www.mysite.com/download/' + select.value;
}
}
}
The above expects the first option to be the default selected, so if it's selected, or no option at all is selected, the select's selectedIndex will be 0 or -1 respsectively. I would ensure one option is selected by adding the selected attribute to the first one:
<option value="default" selected>Select File</option>
and the call is:
<img src="buttonImage.jpg" onclick="download('one', 'two');">
though you might want to add a class to the select elements and get them using getElementsByClassName or similar and loop over that collection, rather than hard code the ids.
Try replacing this:
<p class="button_image">
<a onclick="download(document.getElementById('one').value)"></a>
</p>
with:
<p class="button_image">
<a onclick="download(document.getElementById('one').value, document.getElementById('two').value)"></a>
</p>
and then replace your download function with this:
function download(file1,file2) {
if (file1 == 'default' && file2 == 'default'){
return;
}
else if(file1 != 'default'){
window.location = 'http://www.mysite.com/download/' + file1;
}
else{
window.location = 'http://www.mysite.com/download/' + file2;
}
}

how to Target an option from pull down with js to apply more code

a friend asked me to help him with a form, a client of his wants to make a form a bit more dynamic...my javascript is minimal at best since i just started learning.
He asked me something along the lines of " how can i make a form show another pull down ONLY WHEN a certain option is selected "
in the example he gave me, by default when page loads,he has a pull down menu which has 2 options, MANHATTAN and option two is BROOKLYN.
If Manhattan is chose, that reveals another pull down with zips for manhattan, if Brooklyn is chosen the same for BK.
in sample html, something along the lines like this:
<div>
<form>
<select name="boro" id="boro">
<option value="manhattan" id="manh">Manhattan</option>
<option value="brooklyn" id="brook">Brooklyn</option>
</select>
</form>
<br/>
<div id="empty2fill"></div><!-- for showing chosen results -->
</div>
i want to target/capture the option chosen by the user above on the pull down menu, to then activate this function(below).
according to his request what i guess id do is,(as a newbie), then as far as the .js goes (pseudo code):
<script type="text/javascript">
function valBoro (){
if( brook is chosen){ document.getElementById('empty2fill').innerHTML=" new dropdown code here")
}
}
</script>
aside from not knowing, my main problem is i dont know how to target the option chosen in the menu to thereafter, apply the function (which will be written later)
any ideas, tips etc are greately appreciated.
thanks in advance
Another option is to create the two dropdown lists and set the style display to "none". Then you can catch the onChange event and set display to "" based on the value of the select element.
function showZip() {
var boro = document.getElementById("boro");
if (boro.value == "manhattan") {
var zipManhattan = document.getElementById("zipManhattan");
zipManhattan.style.display = "";
}
}
And in the html
<div>
<select name="boro" id="boro" onchange="javascript:showZip();">
<option value="manhattan" id="manh">Manhattan</option>
<option value="brooklyn" id="brook">Brooklyn</option>
</select>
<br/>
<select name="zipManhattan" id="zipManhattan" style="display:none;">
<option value="zip1" id="zip1">1111</option>
<option value="zip2" id="zip2">2222</option>
</select>
<div id="empty2fill"></div><!-- for showing chosen results -->
</div>
Here is a link to a jsfiddle showing example code.
http://jsfiddle.net/WKqth/
Example markup:
<div>
<form>
<select name="boro" id="boro">
<option value="" id="none">Select a boro.</option>
<option value="manhattan" id="manh">Manhattan</option>
<option value="brooklyn" id="brook">Brooklyn</option>
</select>
</form>
<br/>
<div id="empty2fill"></div><!-- for showing chosen results -->
</div>
Example js
// include this js below the form in the body, or wrap it in a function and assign that to window.onload, or use a library that provides onDomReady (in jQuery, $(document).ready(function () ... });
var selectElement = document.getElementById('boro');
var showBoroSelect = function () {
// find the selected element
var selectedOption = selectElement.options[selectElement.selectedIndex].id,
// find the element that will contain the new drop down
containerElement = document.getElementById('empty2fill'),
// define the html for the manhattan drop down
manhSelectInnerHTML = '<select name="secondary"><option value="derp">manh derp?</option><option value="herp!">manh herp!</option></select>',
// define the html for the brooklyn drown down
brookSelectInnerHTML = '<select name="secondary"><option value="derp">brook derp?</option><option value="herp!">brook herp!</option></select>',
newInnerHTML;
// determine which html to use based on the selection
if (selectedOption === 'manh') {
newInnerHTML = manhSelectInnerHTML;
} else if (selectedOption === 'brook') {
newInnerHTML = brookSelectInnerHTML;
} else {
// no boro was selected, hide the menu
newInnerHTML = '';
}
// set the container to the new innerHTML
containerElement.innerHTML = newInnerHTML;
};
// when the boro select changes, show the new menu
selectElement.onchange = function () {
showBoroSelect();
};
// if you select a boro and reload the page, the boro may already be selected (for example, firefox might do this)
// this will set the boro menu initially before the user changes it
showBoroSelect();
You want to handle the change event of your "boro" select element.
I've put a plain-JS example solution on jsfiddle at http://jsfiddle.net/FHArd/1/
This creates three select lists - one is your "boro" and the other two are the zip code lists, but they are hidden via CSS until a selection is made.
The change event handler simply adds and/or removes classes from the zip code select elements; the CSS hides or shows the lists based on the class "active" that is attached to the zip code select list.
Note - being there in jsfiddle the way you start things up is a little different than normal. You'd really run your setup function at the onload or ondomready event.
This should do it.
<select name="boro" id="boro" onchange="valBoro(this)">
<option value="manhattan" id="manh">Manhattan</option>
<option value="brooklyn" id="brook">Brooklyn</option>
</select>
<script type="text/javascript">
function valBoro(dropDown) {
if (dropDown.options.[dropDown.selectedIndex].value.equals("manhattan")) document.getElementById('empty2fill').innerHTML = "newHTMLCode";
//change "manhattan" to whatever option you want to use
}
</script>

Search a dropdown

I have this HTML dropdown:
<form>
<input type="text" id="realtxt" onkeyup="searchSel()">
<select id="select" name="basic-combo" size="1">
<option value="2821">Something </option>
<option value="2825"> Something </option>
<option value="2842"> Something </option>
<option value="2843"> _Something </option>
<option value="15999"> _Something </option>
</select>
</form>
I need to search trough it using javascript.
This is what I have now:
function searchSel() {
var input=document.getElementById('realtxt').value.toLowerCase();
var output=document.getElementById('basic-combo').options;
for(var i=0;i<output.length;i++) {
var outputvalue = output[i].value;
var output = outputvalue.replace(/^(\s| )+|(\s| )+$/g,"");
if(output.indexOf(input)==0){
output[i].selected=true;
}
if(document.forms[0].realtxt.value==''){
output[0].selected=true;
}
}
}
The code doesn't work, and it's probably not the best.
Can anyone show me how I can search trough the dropdown items and when i hit enter find the one i want, and if i hit enter again give me the next result, using plain javascript?
Here's the fixed code. It searches for the first occurrence only:
function searchSel() {
var input = document.getElementById('realtxt').value;
var list = document.getElementById('select');
var listItems = list.options;
if(input === '')
{
listItems[0].selected = true;
return;
}
for(var i=0;i<list.length;i++) {
var val = list[i].value.toLowerCase();
if(val.indexOf(input) == 0) {
list.selectedIndex = i;
return;
}
}
}
You should not check for empty text outside the for loop.
Also, this code will do partial match i.e. if you type 'A', it will select the option 'Artikkelarkiv' option.
Right of the bat, your code won't work as you're selecting the dropdown wrong:
document.getElementById("basic-combo")
is wrong, as the id is select, while "basic-combo" is the name attribute.
And another thing to note, is that you have two variable named output. Even though they're in different scopes, it might become confusing.
For stuff like this, I'd suggest you use a JavaScript library like jQuery (http://jquery.com) to make DOM interaction easier and cross-browser compatible.
Then, you can select and traverse all the elements from your select like this:
$("#select").each(function() {
var $this = $(this); // Just a shortcut
var value = $this.val(); // The value of the option element
var content = $this.html(); // The text content of the option element
// Process as you wish
});

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