Develop Reference

Shopify Variant Is Not Selected After JS action

Using funnel builder app for Shopify. Got 1 native shopify select item that's choosing variants, 2 other static input methods that I added (radio buttons and input), and JS that pulls input values from these 2 and sets select to it. The problem is- on the front end, it changes select value, but when I add to cart, it's still adding default option.
The select html looks like this.
<select class="form-control variant_Quantity" onchange="change_product_variant(this);" id="select_61">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
</select>
And this is my jQuery
$(".pricelinewrap").each(function(){
$(this).click(function(){
$(this).find("input[type=radio]").prop('checked', 'checked');
var quanval = $(this).find("input[type=radio]").prop('checked', 'checked').val();
$("input[name='quantity']").val(quanval);
$("select#select_62").val(quanval);
});
});
$("input[name='quantity']").change(function(){
var newquanval = $(this).val();
$("select#select_62").val(newquanval);
});
Keep in mind- everything works on the front end. But looks like i'm missing something that the actual variant is not selected. However, select option is shown correctly, when something else is changed.

You have to trigger change event to the select, since the following code:
$("input[name='quantity']").val(quanval);
$("select#select_62").val(quanval);
only changes the value of the select but it doesn't fire the actual change event.
It should become like this:
$("input[name='quantity']").val(quanval).trigger('change');
$("select#select_62").val(quanval).trigger('change');

How do I get the current option values into an array?

Suppose I have a list:
<select>
<option value="Horse">Horse</option>
<option value="Bird">Bird</option>
<option value="Dogs">Dogs</option>
<option value="Cats">Cats</option>
</select>
I know how to grab the values of each option by looping through. My problem is I have code that changes the default values to something if certain conditions are met but if the conditions are not met I need to revert back to the DEFAULT values. I need to get the default values into an array so I can use them to revert back if the conditions are not met...etc. I need pure javascript no frameworks.
So for example if I change <option value="Horse">Horse</option>to <option value="Train">Train</option>I need to be able to store <option value="Horse">Horse</option> BEFORE it gets changed the same way you can get the default value for an input field to revert back to it if needed.

Use following code:
var options = document.querySelectorAll("option");
var optionsArray = Array.prototype.map.call(options, function(x) {
return x.value;
});
<select>
<option value="Horse">Horse</option>
<option value="Bird">Bird</option>
<option value="Dogs">Dogs</option>
<option value="Cats">Cats</option>
</select>

I figured out the solution and that is to get the values on page load and make sure your script is before the closing body tag.

How to select a particular value from a <select> element?

I have come across <select> (drop down list) in HTML in the learning process. I learnt how to code a <select> drop down list.
How can I perform a particular action (in my case I am performing a mathematical operation) when a value in the <select> is chosen?

You can do this a couple of ways.
I would suggest putting a onchange event attribute and give the element an ID.
eg.
<select id ="example1" onchange="example_function()">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
Now that you have done that you can goto your JS and use the follow.
var droplist
var droplist_value
function example_function(){
droplist = document.getElementbyID("example1")
droplist_value = droplist.value
}
You can now use the droplist_value as you want.

Multiple Dynamically-Added Inputs in HTML Form

I'm trying to add hidden input fields using JavaScript, but I did/have not achieved the desired result.
I want to add hidden fields to a form when a user selects a value from a dropdown list. The number of dropdown lists are not the same in this and other similar pages, there might be more or less than two.
I want to add a number of hidden fields when the user select value from the first dropdown list, and if he selects another value from another dropdown list I want to add additional hidden fields, and to save all the hidden fields' values.
Example:
<select id="s1">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
If the user selects "2", I want to add 2 hidden fields:
<select id="s2">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
If the user selects "3" in this second list I want to add three additional hidden fields but saving (preserving) the two hidden fields that was already dynamically added using the "s1" earlier.

Honestly, I have no idea what you are asking...but a quick fix could be using proper syntax for HTML.
i.e.
<select id"s2">
Change to
<select id="s2">

jQuery has the very useful change() function. So you might write something like:
$(document).ready(function(){
$("#s1").change(function(){
var field_value = $(this).val();
// then perhaps:
for(i = 0; i < field_value; i++){
}
// or
if(field_value == 2){
// do something
}
});
})
Hope thats of some use. Dukeland has a very good point above as well.

How to fire a change event on a HTMLSelectElement if the new value is the same as the old?

I have the following markup:
<select onchange="jsFunction()">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
When a user pulls down the combobox and selects the same option that was previously selected (or doesn't change the selection at all), JavaScript doesn't regard it as an onchange event. So, the jsFunction() is not called. But I want the jsFunction() called even in this case. How can I achieve this?

I'd do it like this:
<select onchange="jsFunction()">
<option value="" disabled selected style="display:none;">Label</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
If you want you could have the same label as the first option, which in this case is 1.
Even better: put a label in there for the choices in the box.

You have to add empty option to solve it,
I also can give you one more solution but its up to you that is fine for you or not Because User select default option after selecting other options than jsFunction will be called twice.
<select onChange="jsFunction()" id="selectOpt">
<option value="1" onclick="jsFunction()">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>
function jsFunction(){
var myselect = document.getElementById("selectOpt");
alert(myselect.options[myselect.selectedIndex].value);
}

Just set the selectIndex of the associated <select> tag to -1 as the last step of your processing event.
mySelect = document.getElementById("idlist");
mySelect.selectedIndex = -1;
It works every time, removing the highlight and allowing you to select the same (or different) element again .

Try this. Just add an empty option. This will solve your problem.
<select onchange="jsFunction()">
<option></option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select>​

For this problem, I have finally put a new <i> tag to refresh the select instead. Don't try to trigger an event if the selected option is the same that the one already selected.
If user click on the "refresh" button, I trigger the onchange event of my select with :
const refreshEquipeEl = document.getElementById("refreshEquipe1");
function onClickRefreshEquipe(event){
let event2 = new Event('change');
equipesSelectEl.dispatchEvent(event2);
}
refreshEquipeEl.onclick = onClickRefreshEquipe;
This way, I don't need to try select the same option in my select.

use the "onmouseup" property with each option element. it's verbose, but should work. also, depending on what your function is actually doing, you could arrange things a little differently, assuming the number is important in the handler:
<select>
<option onmouseup="handler()" value="1">1</option> //get selected element in handler
<option onmouseup="handler(2)" value="2">2</option> //explicitly send the value as argument
<option onmouseup="handler(this.value)" value="3">3</option> //same as above, but using the element's value property and allowing for dynamic option value. you could also send "this.innerHTML" or "this.textContent" to the handler, making option value unnecessary
</select>

JavaScript code:
on mousedown event: set selectedIndex property value to -1
on change event: handle event
The only drawback is that when the user clicks on the dropdown list, the currently selected item does not appear selected

It's not firing because the value hasn't "changed". It's the same value. Unfortunately, you can't achieve the desired behaviour using the change event.
You can handle the blur event and do whatever processing you need when the user leaves the select box. That way you can run the code you need even if the user selects the same value.