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How to refresh a select list in html

I have a drop-down list where depending on the selected value, the next drop-down list shows specific values. when changing the value of the first list and then going back to the old value, the second list does not update. keeps the same value selected before. How can I make the second list update to the value I marked as selected by default whenever I change the value of the first list?
I hope you guys were able to understand me, and I thank you for your time.
Here's the code:
<select onchange="showprd('hidevalue', this), showprd2('hidevalue2', this)">
<option value="" disabled selected hidden>Selecione</option>
<option value="0">São Francisco</option>
<option value="1">Bradesco</option>
</select>
<br>
<br>
<select hidden id="hidevalue">
<option value="" disabled selected hidden>Selecione o produto</option>
<option value="pleno">Pleno</option>
<option value="integrado">Integrado</option>
</select>
<select hidden id="hidevalue2">
<option value="" disabled selected hidden>Selecione o produto</option>
<option value="junior">Junior</option>
<option value="senior">Senior</option>
</select>
</body>
<script>
function showprd(id, elementValue) {
document.getElementById(id).style.display = elementValue.value == 0 ? 'block' : 'none';
}
function showprd2(id, elementValue) {
document.getElementById(id).style.display = elementValue.value == 1 ? 'block' : 'none';
}
</script>

TL;DR. Control the input value changes in one place.
Please see the updated snippet below. html structure hasn't been changed, but I've removed the inline js call and updated the id names. JavaScript blocks are commented in details.
In a nut-shell, this code listens for any change to the parent select dropdown. Whenever a change occurs, its child dropdowns will reset their values and toggle their visibility accordingly.
// Assign each dom element to a variable
const primarySelect = document.querySelector('#primary');
const childSelect1 = document.querySelector('#child1');
const childSelect2 = document.querySelector('#child2');
const defaultValues = document.querySelectorAll('.default');
function resetInputs() {
// Reset the child select options to default
defaultValues.forEach(option => option.selected = true);
}
function handlePrimary(e) {
// Reset the child select values whenever the parent value changes
resetInputs();
// `input` value is always a string. Here we're converting it to a number
const val = parseFloat(e.target.value);
// Toggle visibility of child select dropdowns
[childSelect1, childSelect2].
forEach((select, i) => select.style.display = val === i ? 'block' : 'none');
}
primarySelect.addEventListener('change', handlePrimary);
<select id="primary">
<option value="" disabled selected hidden>Selecione</option>
<option value="0">São Francisco</option>
<option value="1">Bradesco</option>
</select>
<br>
<br>
<select hidden id="child1">
<option class="default" value="" disabled selected hidden>Selecione o produto</option>
<option value="pleno">Pleno</option>
<option value="integrado">Integrado</option>
</select>
<select hidden id="child2">
<option class="default" value="" disabled selected hidden>Selecione o produto</option>
<option value="junior">Junior</option>
<option value="senior">Senior</option>
</select>

If I understood correctly, the expected behavior is when the second or third <select> is hidden, the <select> should go back to default (the first <option>?). If so, then remove disabled and hidden from the first <option> of the second and third <select> then add the following:
selectObj.hidden = true;
selectObj.selectedIndex = 0;
The example below has a <form> wrapped around everything (always use a form if you have more than one form control. By using HTMLFormElement interface I rewrote the code and can reference all form controls with very little code. Inline event handlers are garbage so don't do this:
<select id='sel' onchange="lame(this)">
Instead do this:
selObj.onchange = good;
OR
selObj.addEventListener('change', better)
Read about events and event delegation
const UI = document.forms.UI;
UI.onchange = showSelect;
function showSelect(e) {
const sel = e.target;
const IO = this.elements;
if (sel.id === "A") {
if (sel.value === '0') {
IO.B.hidden = false;
IO.C.hidden = true;
IO.C.selectedIndex = 0;
} else {
IO.B.hidden = true;
IO.B.selectedIndex = 0;
IO.C.hidden = false;
}
}
}
<form id='UI'>
<select id='A'>
<option disabled selected hidden>Pick</option>
<option value="0">0</option>
<option value="1">1</option>
</select>
<br>
<br>
<select id="B" hidden>
<option selected>Pick B</option>
<option value="0">0</option>
<option value="1">1</option>
</select>
<select id="C" hidden>
<option selected>Pick C</option>
<option value="0">0</option>
<option value="1">1</option>
</select>
</form>

I give you an example for your reference:
let secondList = [
[{
value: "pleno",
text: "Pleno"
},
{
value: "integrado",
text: "Integrado"
}
],
[
{
value: "junior",
text: "Junior"
},
{
value: "senior",
text: "Senior"
}
]
]
function update(v){
let secondSelectBox=document.getElementById("second");
secondSelectBox.style.display="none";
let optionList=secondList[v.value];
if (optionList){
let defaultOption=new Option("Selecione o produto","");
secondSelectBox.innerHTML="";
secondSelectBox.options.add(defaultOption);
optionList.forEach(o=>{
let vv=new Option(o.text,o.value);
secondSelectBox.options.add(vv);
})
secondSelectBox.style.display="block";
}
}
<select onchange="update(this)">
<option value="" disabled selected hidden>Selecione</option>
<option value="0">São Francisco</option>
<option value="1">Bradesco</option>
</select>
<select hidden id="second">
</select>

How to get data from the drop down menu using javascript? [duplicate]

I have a dropdown list like this:
<select id="box1">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option>
</select>
How can I get the actual option text rather than the value using JavaScript? I can get the value with something like:
<select id="box1" onChange="myNewFunction(this.selectedIndex);" >
But rather than 7122 I want cat.

Try options
function myNewFunction(sel) {
alert(sel.options[sel.selectedIndex].text);
}
<select id="box1" onChange="myNewFunction(this);">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option>
</select>

Plain JavaScript
var sel = document.getElementById("box1");
var text= sel.options[sel.selectedIndex].text;
jQuery:
$("#box1 option:selected").text();

There are two solutions, as far as I know.
both that just need using vanilla javascript
1 selectedOptions
live demo
const log = console.log;
const areaSelect = document.querySelector(`[id="area"]`);
areaSelect.addEventListener(`change`, (e) => {
// log(`e.target`, e.target);
const select = e.target;
const value = select.value;
const desc = select.selectedOptions[0].text;
log(`option desc`, desc);
});
<div class="select-box clearfix">
<label for="area">Area</label>
<select id="area">
<option value="101">A1</option>
<option value="102">B2</option>
<option value="103">C3</option>
</select>
</div>
2 options
live demo
const log = console.log;
const areaSelect = document.querySelector(`[id="area"]`);
areaSelect.addEventListener(`change`, (e) => {
// log(`e.target`, e.target);
const select = e.target;
const value = select.value;
const desc = select.options[select.selectedIndex].text;
log(`option desc`, desc);
});
<div class="select-box clearfix">
<label for="area">Area</label>
<select id="area">
<option value="101">A1</option>
<option value="102">B2</option>
<option value="103">C3</option>
</select>
</div>

All these functions and random things, I think it is best to use this, and do it like this:
this.options[this.selectedIndex].text

HTML:
<select id="box1" onChange="myNewFunction(this);">
JavaScript:
function myNewFunction(element) {
var text = element.options[element.selectedIndex].text;
// ...
}
DEMO: http://jsfiddle.net/6dkun/1/

Use -
$.trim($("select").children("option:selected").text()) //cat
Here is the fiddle - http://jsfiddle.net/eEGr3/

To get it on React with Typescript:
const handleSelectChange: React.ChangeEventHandler<HTMLSelectElement> = (event) => {
const { options, selectedIndex } = event.target;
const text = options[selectedIndex].text;
// Do something...
};

Using jquery.
In your event
let selText = $("#box1 option:selected").text();
console.log(selText);

Using vanilla JavaScript
onChange = { e => e.currentTarget.options[e.selectedIndex].text }
will give you exact value if values are inside a loop.

function runCode() {
var value = document.querySelector('#Country').value;
window.alert(document.querySelector(`#Country option[value=${value}]`).innerText);
}
<select name="Country" id="Country">
<option value="IN">India</option>
<option value="GBR">United Kingdom </option>
<option value="USA">United States </option>
<option value="URY">Uruguay </option>
<option value="UZB">Uzbekistan </option>
</select>
<button onclick="runCode()">Run</button>

You'll need to get the innerHTML of the option, and not its value.
Use this.innerHTML instead of this.selectedIndex.
Edit: You'll need to get the option element first and then use innerHTML.
Use this.text instead of this.selectedIndex.

<select class="cS" onChange="fSel2(this.value);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS1" onChange="fSel(options[this.selectedIndex].value);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select><br>
<select id="iS2" onChange="fSel3(options[this.selectedIndex].text);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS3" onChange="fSel3(options[this.selectedIndex].textContent);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS4" onChange="fSel3(options[this.selectedIndex].label);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS4" onChange="fSel3(options[this.selectedIndex].innerHTML);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<script type="text/javascript"> "use strict";
const s=document.querySelector(".cS");
// options[this.selectedIndex].value
let fSel = (sIdx) => console.log(sIdx,
s.options[sIdx].text, s.options[sIdx].textContent, s.options[sIdx].label);
let fSel2= (sIdx) => { // this.value
console.log(sIdx, s.options[sIdx].text,
s.options[sIdx].textContent, s.options[sIdx].label);
}
// options[this.selectedIndex].text
// options[this.selectedIndex].textContent
// options[this.selectedIndex].label
// options[this.selectedIndex].innerHTML
let fSel3= (sIdx) => {
console.log(sIdx);
}
</script> // fSel
But :
<script type="text/javascript"> "use strict";
const x=document.querySelector(".cS"),
o=x.options, i=x.selectedIndex;
console.log(o[i].value,
o[i].text , o[i].textContent , o[i].label , o[i].innerHTML);
</script> // .cS"
And also this :
<select id="iSel" size="3">
<option value="one">Un</option>
<option value="two">Deux</option>
<option value="three">Trois</option>
</select>
<script type="text/javascript"> "use strict";
const i=document.getElementById("iSel");
for(let k=0;k<i.length;k++) {
if(k == i.selectedIndex) console.log("Selected ".repeat(3));
console.log(`${Object.entries(i.options)[k][1].value}`+
` => ` +
`${Object.entries(i.options)[k][1].innerHTML}`);
console.log(Object.values(i.options)[k].value ,
" => ",
Object.values(i.options)[k].innerHTML);
console.log("=".repeat(25));
}
</script>

You can get an array-like object that contains the selected item(s) with the method getSelected() method. like this:
querySelector('#box1').getSelected()
so you can extract the text with the .textContent attribute. like this:
querySelector('#box1').getSelected()[0].textContent
If you have a multiple selection box you can loop through array-like object
I hope it helps you😎👍

var selectionlist=document.getElementById("agents");
td2.innerHTML = selectionlist.children[selectionlist.selectedIndex].innerHTML;

ECMAScript 6+
const select = document.querySelector("#box1");
const { text } = [...select.options].find((option) => option.selected);

Try the below:
myNewFunction = function(id, index) {
var selection = document.getElementById(id);
alert(selection.options[index].innerHTML);
};
See here jsfiddle sample

how do i innerhtml a select list element in javascript? [duplicate]

I have a dropdown list like this:
<select id="box1">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option>
</select>
How can I get the actual option text rather than the value using JavaScript? I can get the value with something like:
<select id="box1" onChange="myNewFunction(this.selectedIndex);" >
But rather than 7122 I want cat.

Try options
function myNewFunction(sel) {
alert(sel.options[sel.selectedIndex].text);
}
<select id="box1" onChange="myNewFunction(this);">
<option value="98">dog</option>
<option value="7122">cat</option>
<option value="142">bird</option>
</select>

Plain JavaScript
var sel = document.getElementById("box1");
var text= sel.options[sel.selectedIndex].text;
jQuery:
$("#box1 option:selected").text();

There are two solutions, as far as I know.
both that just need using vanilla javascript
1 selectedOptions
live demo
const log = console.log;
const areaSelect = document.querySelector(`[id="area"]`);
areaSelect.addEventListener(`change`, (e) => {
// log(`e.target`, e.target);
const select = e.target;
const value = select.value;
const desc = select.selectedOptions[0].text;
log(`option desc`, desc);
});
<div class="select-box clearfix">
<label for="area">Area</label>
<select id="area">
<option value="101">A1</option>
<option value="102">B2</option>
<option value="103">C3</option>
</select>
</div>
2 options
live demo
const log = console.log;
const areaSelect = document.querySelector(`[id="area"]`);
areaSelect.addEventListener(`change`, (e) => {
// log(`e.target`, e.target);
const select = e.target;
const value = select.value;
const desc = select.options[select.selectedIndex].text;
log(`option desc`, desc);
});
<div class="select-box clearfix">
<label for="area">Area</label>
<select id="area">
<option value="101">A1</option>
<option value="102">B2</option>
<option value="103">C3</option>
</select>
</div>

All these functions and random things, I think it is best to use this, and do it like this:
this.options[this.selectedIndex].text

HTML:
<select id="box1" onChange="myNewFunction(this);">
JavaScript:
function myNewFunction(element) {
var text = element.options[element.selectedIndex].text;
// ...
}
DEMO: http://jsfiddle.net/6dkun/1/

Use -
$.trim($("select").children("option:selected").text()) //cat
Here is the fiddle - http://jsfiddle.net/eEGr3/

To get it on React with Typescript:
const handleSelectChange: React.ChangeEventHandler<HTMLSelectElement> = (event) => {
const { options, selectedIndex } = event.target;
const text = options[selectedIndex].text;
// Do something...
};

Using jquery.
In your event
let selText = $("#box1 option:selected").text();
console.log(selText);

Using vanilla JavaScript
onChange = { e => e.currentTarget.options[e.selectedIndex].text }
will give you exact value if values are inside a loop.

function runCode() {
var value = document.querySelector('#Country').value;
window.alert(document.querySelector(`#Country option[value=${value}]`).innerText);
}
<select name="Country" id="Country">
<option value="IN">India</option>
<option value="GBR">United Kingdom </option>
<option value="USA">United States </option>
<option value="URY">Uruguay </option>
<option value="UZB">Uzbekistan </option>
</select>
<button onclick="runCode()">Run</button>

You'll need to get the innerHTML of the option, and not its value.
Use this.innerHTML instead of this.selectedIndex.
Edit: You'll need to get the option element first and then use innerHTML.
Use this.text instead of this.selectedIndex.

<select class="cS" onChange="fSel2(this.value);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS1" onChange="fSel(options[this.selectedIndex].value);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select><br>
<select id="iS2" onChange="fSel3(options[this.selectedIndex].text);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS3" onChange="fSel3(options[this.selectedIndex].textContent);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS4" onChange="fSel3(options[this.selectedIndex].label);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<select id="iS4" onChange="fSel3(options[this.selectedIndex].innerHTML);">
<option value="0">S?lectionner</option>
<option value="1">Un</option>
<option value="2" selected>Deux</option>
<option value="3">Trois</option>
</select>
<script type="text/javascript"> "use strict";
const s=document.querySelector(".cS");
// options[this.selectedIndex].value
let fSel = (sIdx) => console.log(sIdx,
s.options[sIdx].text, s.options[sIdx].textContent, s.options[sIdx].label);
let fSel2= (sIdx) => { // this.value
console.log(sIdx, s.options[sIdx].text,
s.options[sIdx].textContent, s.options[sIdx].label);
}
// options[this.selectedIndex].text
// options[this.selectedIndex].textContent
// options[this.selectedIndex].label
// options[this.selectedIndex].innerHTML
let fSel3= (sIdx) => {
console.log(sIdx);
}
</script> // fSel
But :
<script type="text/javascript"> "use strict";
const x=document.querySelector(".cS"),
o=x.options, i=x.selectedIndex;
console.log(o[i].value,
o[i].text , o[i].textContent , o[i].label , o[i].innerHTML);
</script> // .cS"
And also this :
<select id="iSel" size="3">
<option value="one">Un</option>
<option value="two">Deux</option>
<option value="three">Trois</option>
</select>
<script type="text/javascript"> "use strict";
const i=document.getElementById("iSel");
for(let k=0;k<i.length;k++) {
if(k == i.selectedIndex) console.log("Selected ".repeat(3));
console.log(`${Object.entries(i.options)[k][1].value}`+
` => ` +
`${Object.entries(i.options)[k][1].innerHTML}`);
console.log(Object.values(i.options)[k].value ,
" => ",
Object.values(i.options)[k].innerHTML);
console.log("=".repeat(25));
}
</script>

You can get an array-like object that contains the selected item(s) with the method getSelected() method. like this:
querySelector('#box1').getSelected()
so you can extract the text with the .textContent attribute. like this:
querySelector('#box1').getSelected()[0].textContent
If you have a multiple selection box you can loop through array-like object
I hope it helps you😎👍

var selectionlist=document.getElementById("agents");
td2.innerHTML = selectionlist.children[selectionlist.selectedIndex].innerHTML;

ECMAScript 6+
const select = document.querySelector("#box1");
const { text } = [...select.options].find((option) => option.selected);

Try the below:
myNewFunction = function(id, index) {
var selection = document.getElementById(id);
alert(selection.options[index].innerHTML);
};
See here jsfiddle sample

Clicking on the first option js

Tell me please, there is a code in which when you click option select, a div element is added with an option value.
But there is a problem, which is that you cannot immediately click on the first option, you must first click on the second, and only after the first. How to fix this problem?
Thank you in advance.
var p = document.getElementById("inputi");
var length = 1;
function add_input_from_select(select) {
var new_input = document.createElement("input");
new_input.name = "my_input";
new_input.value = select.value;
var div = document.createElement('div');
div.innerHTML = '<br>div элемент №' + length + '<br>';
div.appendChild(new_input);
p.appendChild(div);
length++;
}
function add_input_old() {
add_input_from_select(document.getElementById("selector"));
}
<select id="selector" onchange="add_input_from_select(this)">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
<br>
<form>
<div id="inputi"><input name="my_input"></div>
</form>

In html dropdown you can not able to select a value which already selected, so must need to add one more option in your dropdown which say "Please Select" and after that you can able to select any option. That's the right solution
See working example:-
var p = document.getElementById("inputi");
var length = 1;
function add_input_from_select(select) {
var new_input = document.createElement("input");
new_input.name = "my_input";
new_input.value = select.value;
if(!new_input.value) return false;
var div = document.createElement('div');
div.innerHTML = '<br>div элемент №' + length + '<br>';
div.appendChild(new_input);
p.appendChild(div);
length++;
}
function add_input_old() {
add_input_from_select(document.getElementById("selector"));
}
<select id="selector" onchange="add_input_from_select(this)">
<option value="">Please Select</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
<br>
<form>
<div id="inputi"><input name="my_input"></div>
</form>

This happens because you done it with onchange event so the first option is already selected thats why first time it doesn't add div so for overcome that just add one more option to html like
<select id="selector" onchange="add_input_from_select(this)">
<option value="">select Option</option>
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
</select>
and put condition in javascript like,
if(document.getElementById("selector").value != ""){
//add your div here
}
this condition must apply because when you select first option it did not be added like select options.

function needs to wait until select tag's value selected

I have a function in my main.js needs to wait until some options selected on select tag. According to that, I will update the element. I tried to do it with addlistenerevent, but I could not succeed it. Any suggestions? Am I doing wrong?
var test = function() {
const langOptions = {
dummy: 0,
one: 5,
two: 8,
three: 2
};
var unit_1 = 1;
var selectSource ="";
var selectTarget = "";
var section = document.getElementById("unit");
var span_1 = '<span>Unit : </span>';
section.insertAdjacentHTML("beforeend", span_1);
var span_2 = '<span id= "span_2">' + unit_1 +'</span>';
section.insertAdjacentHTML("beforeend", span_2);
document.getElementById('source-lang').addEventListener('change', function() {
selectSource = $('source-lang').find('select').val();
for (const key of Object.keys(langOptions)) {
if (key === selectSource || key === selectTarget) { unitPrice *= langOptions[key];}
}
var element = document.getElementById('span_2').innerHTML = unit_1;
});
};
test();
<div id="langs">
<section class="container">
<div class="dropdown">
<select id="source-lang" style="background-color:#5e3080" name="source-lang">
<option value="">Select</option>
<option value="option1">option1</option>
<option value="option2">option2</option>
<option value="option3">option3</option>
</select>
</div>
<div class="dropdown">
<select id ="target-lang" style="background-color:#5e3080" name="target-lang">
<option value="">Select</option>
<option value="option1">option1</option>
<option value="option2">option2</option>
<option value="option3">option3</option>
</select>
</div>
<div class="dropdown">
<div id="unit"></div>
</div>
</section>
</div>

I think that what you are looking for, is the onchange Event
function selectOne() {
const id = 'selectOne';
console.log(id, document.getElementById(id).value);
}
document.getElementById('selectTwo').addEventListener("change", function() {
console.log(this.id, this.value)
});
<p>Select One</p>
<select id="selectOne" type="text" onchange="selectOne()">
<option value=1>1</option>
<option value=2>2</option>
<option value=3>3</option>
</select>
<!-- Or using addEventListener -->
<p>Select Two</p>
<select id="selectTwo" type="text">
<option value=a>a</option>
<option value=b>b</option>
<option value=c>c</option>
</select>

Use onchange Event
<select id="source-lang" style="background-color:#5e3080" name="source-lang" onchange="test()">
<select id ="target-lang" style="background-color:#5e3080" name="target-lang" onchange="test()">