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how to fill two or more selects with the same option elements

I'd like to add the same options elements to more than one select, using one JavaScript function.
<select id="select1" name="select1"></select>
<select id="select2" name="select2"></select>
I want selects become:
<select id="select1" name="select1">
<option value="0">Txt1</option>
<option value="1">Txt2</option>
<option value="2">Txt3</option>
</select>
<select id="select2" name="select2">
<option value="0">Txt1</option>
<option value="1">Txt2</option>
<option value="2">Txt3</option>
</select>
Here is part of function to fill selects with options:
function window_onload(){
var SpecTxt = new Array("Txt1","Txt2","Txt3");
for(var i=0; i<SpecTxt.length; i++) {
var oOption = document.createElement("OPTION");
oOption.text = SpecTxt[i];
oOption.value=i;
select1.add(oOption); // Option to first SELECT
select2.add(oOption); // Option to second SELECT
}
}
But I've got Internet Explorer Script Error "Invalid argument", result is only one first option in "select1" and no options in "select2". If I remove from function window_onload() the last string select2.add(oOption);, there are no IE errors and "select1" is filled as must be, but "select2" is empty. How is it possible in JS to add the same options to different SELECTs?

Update
The reason why the Demo didn't work for IE is because it doesn't recognize the property .valueAsNumber.
From:
var opts = qty.valueAsNumber;
To:
var opts = parseInt(qty.value, 10);
When you create an option within the loop:
var oOption = document.createElement("OPTION");
That is only one <option> not two <option>s. So that is the reason why:
select1.add(oOption); // Succeeds
select2.add(oOption); // Fails
You can either make 2 <option>s per loop:
var oOption1 = document.createElement("OPTION");
var oOption2 = document.createElement("OPTION");
OR try cloneNode(). See Demo below:
Demo
// See HTMLFormControlsCollection
var form = document.forms.ui;
var ui = form.elements;
var qty = ui.qty0;
var s0 = ui.sel0;
var s1 = ui.sel1;
// Declare a counter variable outside of loop
var cnt = 0;
// Add event handler to the change event of the input
qty.onchange = addOpt;
/* Get the value of user input as a number
|| within the for loop...
|| create an <option> tag...
|| add text to it with an incremented offset...
|| add a incremented value to it...
|| then clone it...
|| add original <option> to the first <select>...
|| add duplicate <option> to the second <select>
*/
function addOpt(e) {
var opts = parseInt(qty.value, 10);
for (let i = 0; i < opts; i++) {
var opt = document.createElement('option');
opt.text = 'Txt' + (cnt + 1);
opt.value = cnt;
var dupe = opt.cloneNode(true);
s0.add(opt);
s1.add(dupe);
cnt++;
}
}
input,
select,
option {
font: inherit
}
input {
width: 4ch;
}
<form id='ui'>
<fieldset>
<legend>Enter a number in the first form field</legend>
<input id='qty0' name='qty0' type='number' min='0' max='30'>
<select id="sel0" name="sel0"></select>
<select id="sel1" name="sel1"></select>
</fieldset>
</form>
Reference
HTMLFormControlsCollection

How to populate select options from an array based on a select value?

Trying to get my second select element's options to populate from an array based on the value of the first select element. I can't seem to understand why it only populates the items from the array of the first select element. I know the appendChild is causing the items to keep tacking on at the need, but I've tried to clear the variables, but it seems the option elements that were created stay.
Any help would be great, thanks!
<select id="makeSelect" onChange="modelAppend()">
<option value="merc">Mercedes</option>
<option value="audi">Audi</option>
<option value="bmw">BMW</option>
</select>
<select id="modelSelect">
</select>
<script>
var audiModels = ["TT", "R8", "A4", "A6"]; //audimodels
var mercModels = ["C230", "B28", "LTX",]; //mercmodels
var bmwModels = ["328", "355", "458i",]; //bmwmodels
var selectedMake = document.getElementById("makeSelect"); //grabs the make select
var selectedModel = document.getElementById("modelSelect"); //grabs the model select
var appendedModel = window[selectedMake.value + "Models"]; // appends "Models" to selectedMake.value and converts string into variable
function modelAppend() {
for (var i = 0; i < appendedModel.length; i ++) { // counts items in model array
var models = appendedModel[i]; // // sets "models" to count of model array
var modelOptions = document.createElement("option"); //create the <option> tag
modelOptions.textContent = models; // assigns text to option
modelOptions.value = models; // assigns value to option
selectedModel.appendChild(modelOptions); //appeneds option tag with text and value to "modelSelect" element
}
}
</script>

This line is fishy:
var appendedModel = window[selectedMake.value + "Models"];
You need to get the element when the value has changed, not on page load. Then you need to remove the options on change too, or you will get a very long list if the user selects multiple times. Use an object to store the arrays, that makes it much easier to access them later. Also better use an event listener instead of inline js (though that's not the main problem here).
Try below code:
let models = {
audiModels: ["TT", "R8", "A4", "A6"],
mercModels: ["C230", "B28", "LTX"],
bmwModels: ["328", "355", "458i"]
}
document.getElementById('makeSelect').addEventListener('change', e => {
let el = e.target;
let val = el.value + 'Models';
let appendTo = document.getElementById('modelSelect');
Array.from(appendTo.getElementsByTagName('option')).forEach(c => appendTo.removeChild(c));
if (!models[val] || !Array.isArray(models[val])) {
appendTo.style.display = 'none';
return;
}
models[val].forEach(m => {
let opt = document.createElement('option');
opt.textContent = opt.value = m;
appendTo.appendChild(opt);
});
appendTo.style.display = '';
});
<select id="makeSelect">
<option value=""></option>
<option value="merc">Mercedes</option>
<option value="audi">Audi</option>
<option value="bmw">BMW</option>
</select>
<select id="modelSelect" style="display:none">
</select>

Using jquery data attributes with each function

I'm building a quote generator, and there is a product field where a user can select a product, select the quantity, then add another if they wish.
I'm using an each function to loop through all the products they add to sum the price.
For regular values, my JS is running great, but I want to add a second price (minimum price) that the product can be sold for. I've added the data as an attribute and i'm trying to use the same method to pull the price from the attribute, but it just keeps returning 'undefined'!!!!
HTML
<select class="form-control onChangePrice system1" name="SystemModel">
<option value="">Select...</option>
<option value="3300" data-min-price="3000">System 1</option>
<option value="4500" data-min-price="4000">System 2</option>
<option value="6000" data-min-price="5500">System 3</option>
<option value="6000" data-min-price="5500">System 4</option>
</select>
<div class="col-lg-3 col-md-3 col-sm-3">
<input class="form-control onChangePrice systemNumber" type="number" name="SystemModelAmount" value="1">
</div>
JS
var systemTotal = 0;
var systemMin = 0;
var i = 0;
$('.system1').each(function(){
if (this.value != "") {
systemEachMin = $(this).data("minPrice");
console.log(systemEachMin);
systemEachTotal = this.value * parseInt($(".systemNumber").eq(i).val());
systemTotal += parseFloat(systemEachTotal);
systemMin += parseFloat(systemEachMin);
};
i++;
});
The code works flawlessly for the regular value of the option, i just cant get it to repeat for the data attribute!
Thanks

You're doing a couple of things slightly wrong here:
$('.system1').each(function(){
should be:
$('.system1 option').each(function(){
and
systemEachMin = $(this).data("minPrice");
should be:
systemEachMin = $(this).data("min-price");
So in full:
var systemTotal = 0;
var systemMin = 0;
var i = 0;
$('.system1 option').each(function(){
if (this.value != "") {
systemEachMin = $(this).data("min-price");
console.log(systemEachMin);
systemEachTotal = this.value * parseInt($(".systemNumber").eq(i).val());
systemTotal += parseFloat(systemEachTotal);
systemMin += parseFloat(systemEachMin);
};
i++;
});

$(this).data("minPrice"); refers to the select tag and not the options tag, there is no data-min-price on the select tag.
this.options will return all the options in an array
or you could use the following for the selected options data attribute
$(this).find('option:selected').data("minPrice")
or
$("option:selected", this).data("minPrice")

How to compare <option> “data-names” in an “if” statement?

I have a slight issue. I have options with a “value” and a “data-name”.
<option value=”A” data-name1=”X”>
<option value=”B” data-name1=”Y”>
I want the computer return a specific value if the selected option is a certain “data-name”
Say there are 2 “data-names”, X and Y.
How can I compare the data-name of the selected option to the 2 data-names, X and Y, to find out which one it is?
I’m thinking something along the lines of this:
var data_name1 = e.options[e.selectedIndex].dataset.name1;
if (data_name1 == “X”) {
…
}
else if (data_name == “Y”) {
…
}
else {
…
}
Is this possible?
Thanks!
Full code---
<script>
document.getElementById("selectElement").selectedIndex = -1; // so that no option //is selected when the page is loaded
function getData(){
var e = document.getElementById("qwert"); // get the <select> element
var data_name1 = e.options[e.selectedIndex].dataset.name1; // get the selected //<option> and its name1 data attribute
// var data_name2 = e.options[e.selectedIndex].dataset.name2; get the selected //<option> and its name2 data attribute
var value = e.options[e.selectedIndex].value; // get the value of the selected <option>
//Result
document.getElementById("data1").innerHTML = data_name1;
document.getElementById("value").innerHTML = value;
}
</script>
<select id="qwert" onclick="getData ()">
<option value="135" data-name1="M">A</option>
<option value="150" data-name1="R">B</option>
<option value="51" data-name1="R">C</option>
<option value="27" data-name1="M">D</option>
</select>
<p>
<label>data-name1 = </label>
<span>"</span><span id="data1"></span><span>"</span>
</p>
<p>
<label>value = </label>
<span>"</span><span id="value"></span><span>"</span>
</p>

You need to use the == operator to compare objects.
= is an assignment expression.
if (data_name1 == “X”) {
// Operations if data_name is equal to X
}
else if (data_name == “Y”) {
// Operations is data_name is equal to Y
}
else {
}

Search and get backup removed element

I have created a javascript search in select element.
option tag does not get any CSS to hide or display none, for this solution I have removed unmatched option and make a backup for removed option for reset list button.
It's working fine but I have a problem, I have about 19000 option for this select list.
search works fine but when I hit reset button, only 9500 option from 19000 comes back.
I appreciate your help.
Here is the code:
CodePen Demo
HTML
<h1>Search in select "option" tag</h1>
<select multiple name="selectMenu" id="selectMenu" style="width:100px" size=10>
<option value ="item 1">item 1</option>
<option value ="item 2">item 2</option>
<option value ="thing 3">thing 3</option>
<option value ="item 4">item 4</option>
<option value ="stuff 5">stuff 5</option>
<option value ="stuff 6">stuff 6</option>
<option value ="stuff 7">stuff 7</option>
<option value ="item 8">item 8</option>
</select>
<p>Search within this list</p>
<input type=text name="search" id="search" onkeypress="searchItems();">
<br>
<input type=button value="Search" onclick="searchItems();">
<input type=button value="Reset List" onclick="resetList();">
Javascript
var itemList = null;
var itemListOriginal = new Array();
var backup = false;
function searchItems() {
itemList = document.getElementById("selectMenu");
var searchStrObj = document.getElementById("search");
var itemDescription = "";
// replace white space with wild card
var searchString = searchStrObj.value;
searchString = searchString.replace(" ", ".*");
var re = new RegExp("(" + searchString + ")", "i"); //"i" sets "ignore case" flag
if (itemListOriginal.length < 1)
backup = true;
else
backup = false;
// loop through options and check for matches
for (i=itemList.options.length - 1; i >=0 ; i--) {
itemDescription = itemList.options.item(i).text;
if (backup) {
hash = new Array();
hash['name'] = itemDescription;
hash['value'] = itemList.options.item(i).value;
itemListOriginal[i] = hash;
}
if (!itemDescription.match(re)) {
itemList.remove(i);
}
}
return false;
}
function resetList() {
//hack! remove all elements from list before repopulating
for (i=itemList.options.length - 1; i >=0 ; i--) {
itemList.remove(i);
}
for (i=0; i < itemListOriginal.length; i++) {
hash = itemListOriginal[i];
//option = new Option(hash['name'], hash['value']); REMOVED
//itemList.options.add(option, i); REMOVED
itemList.options[i] = new Option(hash['name'], hash['value'], false, false);
}
document.getElementById("search").value = "";
}

DEMO
I've observed that in your code backup is changed every time you call the function searchitems().
Thus erasing the old values that were stored in it.
So I've changed that
It is working fine but I have a problem,
I have about 19000 option for this select list.
search works fine but when I hit reset button,
only 9500 option from 19000 comes back.
That is the reason behind that. So I've modified your code and added a global variable backupList in that.
so when the unwanted elements are removed old elements aren't deleted in my code but instead, new removed elements are appended to old removed elements using += shorthand operator.
also rather creating options dynamically and using .add or .append or any similar javascript method I'm using .innerHTML for simplicity as you can see in the code. only problem is that now after you click reset elements will not be sorted as it was in the first case, You'll need to sort them believe me it is easy. for sorting refer: sort select menu alphabetically?.
var itemList = null;
var itemListOriginal = new Array();
var backup = false;
var backupList =""; // To store removed elements
function searchItems() {
itemList = document.getElementById("selectMenu");
var searchStrObj = document.getElementById("search");
var itemDescription = "";
var searchString = searchStrObj.value;
searchString = searchString.replace(" ", ".*");
var re = new RegExp("(" + searchString + ")", "i"); //"i" sets "ignore case" flag
for (i=itemList.options.length - 1; i >=0 ; i--) {
itemDescription = itemList.options.item(i).text;
var hash = new Array();
hash['name'] = itemDescription;
hash['value'] = itemList.options.item(i).value;
itemListOriginal[i] = hash;
if (!itemDescription.match(re)) {
itemList.remove(i); //Remove Unwanted Elements
backupList+="<option value='"+ hash['value']+"'>"+itemDescription+"</option>";
/* append new unwanted elements with previous,
initially it is blank "".
This is Important
*/
}
}
return false;
}
function resetList() {
var itemList = document.getElementById("selectMenu");
itemList.innerHTML+=backupList; /* Add removed elements to list.
alternate to .append,.add or similar function*/
backupList=""; // Make Backup Empty!
document.getElementById("search").value = "";
}
Hope it helps! cheers :)!