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I am trying to make it possible in a "normal" html select element to pick more than one option.
And yes: I know that there's an attribute for the select element called "multiple" which makes this possible by creating a scrollable list with a customizable height.
However, this is not what I'm looking for. I don't want a scrollable list, but rather the drop-down list of a "singular" select to show up when activated and then one should be able to pick multiple option with ctrl button pressed down. Ideally, the drop-down list should disappear when one disengages the ctrl button.
Is there some way of overriding the default eventlistener to make a behaviour like this?
Here's what I've tried so far:
<!DOCTYPE HTML>
<meta charset="UTF-8">
<html>
<head>
</head>
<body>
<select id="varSel" name="varSel">
<option value="1">Variable 1</option>
<option value="2">Variable 2</option>
<option value="3">Variable 3</option>
<option value="4">Variable 4</option>
<option value="5">Variable 5</option>
</select>
<script>
let varSelector = document.getElementById("varSel");
var str = "";
var choices = [];
document.body.addEventListener('keydown', function(event)
{
const key = event.key;
if(key === "Control"){
str = "ctrlDown"
}
});
document.body.addEventListener('keyup', function(event)
{
const key = event.key;
if(key === "Control"){
str = "ctrlUp"
}
});
varSelector.addEventListener("change", function() {
var v = varSel.value;
if(str === "ctrlDown"){
choices.push(v);
console.log(choices);
/* Here I need some code to keep all the previous selected options
marked and prevent the drop-down list from hiding after selecting */
}
else{
choices = [v];
console.log(choices[0]);
}
event.preventDefault();
}, false);
</script>
</body>
</html>
Any help or advice is much appreciated, thanks.
May I suggest a different approach? You can still use the multiple attribute and add event listeners for the focus and blur events, which will modify the size attribute:
const mySelect = document.querySelector('#varSel');
mySelect.addEventListener('focus', () => {
const options = mySelect.querySelectorAll('option');
mySelect.setAttribute('size', options.length);
});
mySelect.addEventListener('blur', () => {
mySelect.setAttribute('size', 1);
})
<select id="varSel" name="varSel" size="1" multiple>
<option value="1">Variable 1</option>
<option value="2">Variable 2</option>
<option value="3">Variable 3</option>
<option value="4">Variable 4</option>
<option value="5">Variable 5</option>
</select>
How do I get the selected value from a dropdown list using JavaScript?
<form>
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
</form>
Given a select element that looks like this:
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
Running this code:
var e = document.getElementById("ddlViewBy");
var value = e.value;
var text = e.options[e.selectedIndex].text;
Results in:
value == 2
text == "test2"
Interactive example:
var e = document.getElementById("ddlViewBy");
function onChange() {
var value = e.value;
var text = e.options[e.selectedIndex].text;
console.log(value, text);
}
e.onchange = onChange;
onChange();
<form>
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
</form>
Plain JavaScript:
var e = document.getElementById("elementId");
var value = e.options[e.selectedIndex].value;
var text = e.options[e.selectedIndex].text;
jQuery:
$("#elementId :selected").text(); // The text content of the selected option
$("#elementId").val(); // The value of the selected option
AngularJS: (http://jsfiddle.net/qk5wwyct):
// HTML
<select ng-model="selectItem" ng-options="item as item.text for item in items">
</select>
<p>Text: {{selectItem.text}}</p>
<p>Value: {{selectItem.value}}</p>
// JavaScript
$scope.items = [{
value: 'item_1_id',
text: 'Item 1'
}, {
value: 'item_2_id',
text: 'Item 2'
}];
var strUser = e.options[e.selectedIndex].value;
This is correct and should give you the value.
Is it the text you're after?
var strUser = e.options[e.selectedIndex].text;
So you're clear on the terminology:
<select>
<option value="hello">Hello World</option>
</select>
This option has:
Index = 0
Value = hello
Text = Hello World
The following code exhibits various examples related to getting/putting of values from input/select fields using JavaScript.
Source Link
Working Javascript & jQuery Demo
<select id="Ultra" onchange="run()"> <!--Call run() function-->
<option value="0">Select</option>
<option value="8">text1</option>
<option value="5">text2</option>
<option value="4">text3</option>
</select><br><br>
TextBox1<br>
<input type="text" id="srt" placeholder="get value on option select"><br>
TextBox2<br>
<input type="text" id="rtt" placeholder="Write Something !" onkeyup="up()">
The following script is getting the value of the selected option and putting it in text box 1
<script>
function run() {
document.getElementById("srt").value = document.getElementById("Ultra").value;
}
</script>
The following script is getting a value from a text box 2 and alerting with its value
<script>
function up() {
//if (document.getElementById("srt").value != "") {
var dop = document.getElementById("srt").value;
//}
alert(dop);
}
</script>
The following script is calling a function from a function
<script>
function up() {
var dop = document.getElementById("srt").value;
pop(dop); // Calling function pop
}
function pop(val) {
alert(val);
}?
</script>
var selectedValue = document.getElementById("ddlViewBy").value;
If you ever run across code written purely for Internet Explorer you might see this:
var e = document.getElementById("ddlViewBy");
var strUser = e.options(e.selectedIndex).value;
Running the above in Firefox et al will give you an 'is not a function' error, because Internet Explorer allows you to get away with using () instead of []:
var e = document.getElementById("ddlViewBy");
var strUser = e.options[e.selectedIndex].value;
The correct way is to use square brackets.
Use:
<select id="Ultra" onchange="alert(this.value)">
<option value="0">Select</option>
<option value="8">text1</option>
<option value="5">text2</option>
<option value="4">text3</option>
</select>
Any input/form field can use a “this” keyword when you are accessing it from inside the element. This eliminates the need for locating a form in the DOM tree and then locating this element inside the form.
There are two ways to get this done either using JavaScript or jQuery.
JavaScript:
var getValue = document.getElementById('ddlViewBy').selectedOptions[0].value;
alert (getValue); // This will output the value selected.
OR
var ddlViewBy = document.getElementById('ddlViewBy');
var value = ddlViewBy.options[ddlViewBy.selectedIndex].value;
var text = ddlViewBy.options[ddlViewBy.selectedIndex].text;
alert (value); // This will output the value selected
alert (text); // This will output the text of the value selected
jQuery:
$("#ddlViewBy:selected").text(); // Text of the selected value
$("#ddlViewBy").val(); // Outputs the value of the ID in 'ddlViewBy'
Beginners are likely to want to access values from a select with the NAME attribute rather than ID attribute. We know all form elements need names, even before they get ids.
So, I'm adding the getElementsByName() solution just for new developers to see too.
NB. names for form elements will need to be unique for your form to be usable once posted, but the DOM can allow a name be shared by more than one element. For that reason consider adding IDs to forms if you can, or be explicit with form element names my_nth_select_named_x and my_nth_text_input_named_y.
Example using getElementsByName:
var e = document.getElementsByName("my_select_with_name_ddlViewBy")[0];
var strUser = e.options[e.selectedIndex].value;
Just use
$('#SelectBoxId option:selected').text(); for getting the text as listed
$('#SelectBoxId').val(); for getting the selected index value
I don't know if I'm the one that doesn't get the question right, but this just worked for me:
Use an onchange() event in your HTML, for example.
<select id="numberToSelect" onchange="selectNum()">
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
JavaScript
function selectNum() {
var strUser = document.getElementById("numberToSelect").value;
}
This will give you whatever value is on the select dropdown per click.
Using jQuery:
$('select').val();
The previous answers still leave room for improvement because of the possibilities, the intuitiveness of the code, and the use of id versus name. One can get a read-out of three data of a selected option -- its index number, its value and its text. This simple, cross-browser code does all three:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Demo GetSelectOptionData</title>
</head>
<body>
<form name="demoForm">
<select name="demoSelect" onchange="showData()">
<option value="zilch">Select:</option>
<option value="A">Option 1</option>
<option value="B">Option 2</option>
<option value="C">Option 3</option>
</select>
</form>
<p id="firstP"> </p>
<p id="secondP"> </p>
<p id="thirdP"> </p>
<script>
function showData() {
var theSelect = demoForm.demoSelect;
var firstP = document.getElementById('firstP');
var secondP = document.getElementById('secondP');
var thirdP = document.getElementById('thirdP');
firstP.innerHTML = ('This option\'s index number is: ' + theSelect.selectedIndex + ' (Javascript index numbers start at 0)');
secondP.innerHTML = ('Its value is: ' + theSelect[theSelect.selectedIndex].value);
thirdP.innerHTML = ('Its text is: ' + theSelect[theSelect.selectedIndex].text);
}
</script>
</body>
</html>
Live demo: http://jsbin.com/jiwena/1/edit?html,output .
id should be used for make-up purposes. For functional form purposes, name is still valid, also in HTML5, and should still be used. Lastly, mind the use of square versus round brackets in certain places. As was explained before, only (older versions of) Internet Explorer will accept round ones in all places.
Another solution is:
document.getElementById('elementId').selectedOptions[0].value
The simplest way to do this is:
var value = document.getElementById("selectId").value;
You can use querySelector.
E.g.
var myElement = document.getElementById('ddlViewBy');
var myValue = myElement.querySelector('[selected]').value;
Running example of how it works:
var e = document.getElementById("ddlViewBy");
var val1 = e.options[e.selectedIndex].value;
var txt = e.options[e.selectedIndex].text;
document.write("<br />Selected option Value: "+ val1);
document.write("<br />Selected option Text: "+ txt);
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2">test2</option>
<option value="3" selected="selected">test3</option>
</select>
Note: The values don't change as the dropdown is changed, if you require that functionality then an onClick change is to be implemented.
To go along with the previous answers, this is how I do it as a one-liner. This is for getting the actual text of the selected option. There are good examples for getting the index number already. (And for the text, I just wanted to show this way)
let selText = document.getElementById('elementId').options[document.getElementById('elementId').selectedIndex].text
In some rare instances you may need to use parentheses, but this would be very rare.
let selText = (document.getElementById('elementId')).options[(document.getElementById('elementId')).selectedIndex].text;
I doubt this processes any faster than the two line version. I simply like to consolidate my code as much as possible.
Unfortunately this still fetches the element twice, which is not ideal. A method that only grabs the element once would be more useful, but I have not figured that out yet, in regards to doing this with one line of code.
I have a bit different view of how to achieve this. I'm usually doing this with the following approach (it is an easier way and works with every browser as far as I know):
<select onChange="functionToCall(this.value);" id="ddlViewBy">
<option value="value1">Text one</option>
<option value="value2">Text two</option>
<option value="value3">Text three</option>
<option value="valueN">Text N</option>
</select>
In 2015, in Firefox, the following also works.
e.options.selectedIndex
In more modern browsers, querySelector allows us to retrieve the selected option in one statement, using the :checked pseudo-class. From the selected option, we can gather whatever information we need:
const opt = document.querySelector('#ddlViewBy option:checked');
// opt is now the selected option, so
console.log(opt.value, 'is the selected value');
console.log(opt.text, "is the selected option's text");
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
event.target.value inside the onChange callback did the trick for me.
Most answers here get the value of the "this" select menu onchange by a plain text JavaScript selector.
For example:
document.getElementById("ddlViewBy").value;
This is not a DRY approach.
DRY (three lines of code):
function handleChange(e) {
let innerText = e.target[e.target.options.selectedIndex].innerText;
let value = e.target.value;
/* Do something with these values */
}
Get the first select option:
console.log(e.target[0]); /* Output: <option value="value_hello">Hello innerText</option>*/
With this idea in mind, we dynamically return a "this" select option item (by selectedIndex):
e.target[e.target.options.selectedIndex].innerText;
Demo
let log = document.getElementById('log');
function handleChange(e) {
let innerText = e.target[e.target.options.selectedIndex].innerText;
let value = e.target.value;
log.innerHTML = `<table>
<tr><th>value</th><th>innerText</th></tr>
<tr><td>${value}</td><td>${innerText}</td></tr>
</table>`;
}
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/milligram/1.4.1/milligram.css">
<select id="greet" onchange="handleChange(event)">
<option value="value_hello">Hello innerText</option>
<option value="value_goodbye">Goodbye innerText</option>
<option value="value_seeYou">See you... innerText</option>
</select>
<select id="other_select_menu" onchange="handleChange(event)">
<option value="value_paris">Paris innerText</option>
<option value="value_ny">New York innerText</option>
</select>
<div id="log"></div>
Here is a JavaScript code line:
var x = document.form1.list.value;
Assuming that the dropdown menu named list name="list" and included in a form with name attribute name="form1".
I think you can attach an event listener to the select tag itself e.g:
<script>
document.addEventListener("DOMContentLoaded", (_) => {
document.querySelector("select").addEventListener("change", (e) => {
console.log(e.target.value);
});
});
</script>
In this scenario, you should make sure you have a value attribute for all of your options, and they are not null.
You should be using querySelector to achieve this. This also standardizes the way of getting a value from form elements.
var dropDownValue = document.querySelector('#ddlViewBy').value;
Fiddle: https://jsfiddle.net/3t80pubr/
Try
ddlViewBy.value // value
ddlViewBy.selectedOptions[0].text // label
console.log( ddlViewBy.value );
console.log( ddlViewBy.selectedOptions[0].text );
<select id="ddlViewBy">
<option value="1">Happy</option>
<option value="2">Tree</option>
<option value="3" selected="selected">Friends</option>
</select>
Here's an easy way to do it in an onchange function:
event.target.options[event.target.selectedIndex].dataset.name
<select name="test" id="test" >
<option value="1" full-name="Apple">A</option>
<option value="2" full-name="Ball">B</option>
<option value="3" full-name="Cat" selected>C</option>
</select>
var obj = document.getElementById('test');
obj.options[obj.selectedIndex].value; //3
obj.options[obj.selectedIndex].text; //C
obj.options[obj.selectedIndex].getAttribute('full-name'); //Cat
obj.options[obj.selectedIndex].selected; //true
There is a workaround, using the EasyUI framework with all of its plugins.
You only need to add some EasyUI object that can read from an input as a "bridge" to the drop-down menu.
Example: easyui-searchbox
To the left, the drop-down, to the right, the easyui-searchbox:
...
<input id="ss" class="easyui-searchbox" style="width:300px"
data-options=" searcher:my_function,
prompt:'Enter value',
menu:'#mm'">
<div id="mm" style="width:200px">
<div data-options="name:'1'">test1</div>
<div data-options="name:'2'">test2</div>
</div>
...
...
<script type="text/javascript">
function my_js_function(triggeredByButton = false){
// normal text of the searchbox (what you entered)
var value = $("#ss").searchbox("getValue");
// what you chose from the drop-down menu
var name = $("#ss").searchbox("getName");
...
Mind: the var name is the '1' or '2', that is, the "value of the drop-down", while var value is the value that was entered in the easyui-searchbox instead and not relevant if you only want to know the value of the drop-down.
I checked how EasyUI fetches that #mm name, and I could not find out how to get that name without the help of EasyUI. The jQuery behind getName:
getName:function(jq){
return $.data(jq[0],"searchbox").searchbox.find("input.textbox-value").attr("name");
}
Mind that the return of this function is not the value of the easyui-searchbox, but the name of the #mm drop-down that was used as the menu parameter of the easyui-searchbox. Somehow EasyUI must get that other value, therefore it must be possible.
If you do not want any plugin to be seen, make it as tiny as possible? Or find perhaps a plugin that does not need a form at all in the link above, I just did not take the time.
How do I get the selected value from a dropdown list using JavaScript?
<form>
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
</form>
Given a select element that looks like this:
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
Running this code:
var e = document.getElementById("ddlViewBy");
var value = e.value;
var text = e.options[e.selectedIndex].text;
Results in:
value == 2
text == "test2"
Interactive example:
var e = document.getElementById("ddlViewBy");
function onChange() {
var value = e.value;
var text = e.options[e.selectedIndex].text;
console.log(value, text);
}
e.onchange = onChange;
onChange();
<form>
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
</form>
Plain JavaScript:
var e = document.getElementById("elementId");
var value = e.options[e.selectedIndex].value;
var text = e.options[e.selectedIndex].text;
jQuery:
$("#elementId :selected").text(); // The text content of the selected option
$("#elementId").val(); // The value of the selected option
AngularJS: (http://jsfiddle.net/qk5wwyct):
// HTML
<select ng-model="selectItem" ng-options="item as item.text for item in items">
</select>
<p>Text: {{selectItem.text}}</p>
<p>Value: {{selectItem.value}}</p>
// JavaScript
$scope.items = [{
value: 'item_1_id',
text: 'Item 1'
}, {
value: 'item_2_id',
text: 'Item 2'
}];
var strUser = e.options[e.selectedIndex].value;
This is correct and should give you the value.
Is it the text you're after?
var strUser = e.options[e.selectedIndex].text;
So you're clear on the terminology:
<select>
<option value="hello">Hello World</option>
</select>
This option has:
Index = 0
Value = hello
Text = Hello World
The following code exhibits various examples related to getting/putting of values from input/select fields using JavaScript.
Source Link
Working Javascript & jQuery Demo
<select id="Ultra" onchange="run()"> <!--Call run() function-->
<option value="0">Select</option>
<option value="8">text1</option>
<option value="5">text2</option>
<option value="4">text3</option>
</select><br><br>
TextBox1<br>
<input type="text" id="srt" placeholder="get value on option select"><br>
TextBox2<br>
<input type="text" id="rtt" placeholder="Write Something !" onkeyup="up()">
The following script is getting the value of the selected option and putting it in text box 1
<script>
function run() {
document.getElementById("srt").value = document.getElementById("Ultra").value;
}
</script>
The following script is getting a value from a text box 2 and alerting with its value
<script>
function up() {
//if (document.getElementById("srt").value != "") {
var dop = document.getElementById("srt").value;
//}
alert(dop);
}
</script>
The following script is calling a function from a function
<script>
function up() {
var dop = document.getElementById("srt").value;
pop(dop); // Calling function pop
}
function pop(val) {
alert(val);
}?
</script>
var selectedValue = document.getElementById("ddlViewBy").value;
If you ever run across code written purely for Internet Explorer you might see this:
var e = document.getElementById("ddlViewBy");
var strUser = e.options(e.selectedIndex).value;
Running the above in Firefox et al will give you an 'is not a function' error, because Internet Explorer allows you to get away with using () instead of []:
var e = document.getElementById("ddlViewBy");
var strUser = e.options[e.selectedIndex].value;
The correct way is to use square brackets.
Use:
<select id="Ultra" onchange="alert(this.value)">
<option value="0">Select</option>
<option value="8">text1</option>
<option value="5">text2</option>
<option value="4">text3</option>
</select>
Any input/form field can use a “this” keyword when you are accessing it from inside the element. This eliminates the need for locating a form in the DOM tree and then locating this element inside the form.
There are two ways to get this done either using JavaScript or jQuery.
JavaScript:
var getValue = document.getElementById('ddlViewBy').selectedOptions[0].value;
alert (getValue); // This will output the value selected.
OR
var ddlViewBy = document.getElementById('ddlViewBy');
var value = ddlViewBy.options[ddlViewBy.selectedIndex].value;
var text = ddlViewBy.options[ddlViewBy.selectedIndex].text;
alert (value); // This will output the value selected
alert (text); // This will output the text of the value selected
jQuery:
$("#ddlViewBy:selected").text(); // Text of the selected value
$("#ddlViewBy").val(); // Outputs the value of the ID in 'ddlViewBy'
Beginners are likely to want to access values from a select with the NAME attribute rather than ID attribute. We know all form elements need names, even before they get ids.
So, I'm adding the getElementsByName() solution just for new developers to see too.
NB. names for form elements will need to be unique for your form to be usable once posted, but the DOM can allow a name be shared by more than one element. For that reason consider adding IDs to forms if you can, or be explicit with form element names my_nth_select_named_x and my_nth_text_input_named_y.
Example using getElementsByName:
var e = document.getElementsByName("my_select_with_name_ddlViewBy")[0];
var strUser = e.options[e.selectedIndex].value;
Just use
$('#SelectBoxId option:selected').text(); for getting the text as listed
$('#SelectBoxId').val(); for getting the selected index value
I don't know if I'm the one that doesn't get the question right, but this just worked for me:
Use an onchange() event in your HTML, for example.
<select id="numberToSelect" onchange="selectNum()">
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
JavaScript
function selectNum() {
var strUser = document.getElementById("numberToSelect").value;
}
This will give you whatever value is on the select dropdown per click.
Using jQuery:
$('select').val();
The previous answers still leave room for improvement because of the possibilities, the intuitiveness of the code, and the use of id versus name. One can get a read-out of three data of a selected option -- its index number, its value and its text. This simple, cross-browser code does all three:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Demo GetSelectOptionData</title>
</head>
<body>
<form name="demoForm">
<select name="demoSelect" onchange="showData()">
<option value="zilch">Select:</option>
<option value="A">Option 1</option>
<option value="B">Option 2</option>
<option value="C">Option 3</option>
</select>
</form>
<p id="firstP"> </p>
<p id="secondP"> </p>
<p id="thirdP"> </p>
<script>
function showData() {
var theSelect = demoForm.demoSelect;
var firstP = document.getElementById('firstP');
var secondP = document.getElementById('secondP');
var thirdP = document.getElementById('thirdP');
firstP.innerHTML = ('This option\'s index number is: ' + theSelect.selectedIndex + ' (Javascript index numbers start at 0)');
secondP.innerHTML = ('Its value is: ' + theSelect[theSelect.selectedIndex].value);
thirdP.innerHTML = ('Its text is: ' + theSelect[theSelect.selectedIndex].text);
}
</script>
</body>
</html>
Live demo: http://jsbin.com/jiwena/1/edit?html,output .
id should be used for make-up purposes. For functional form purposes, name is still valid, also in HTML5, and should still be used. Lastly, mind the use of square versus round brackets in certain places. As was explained before, only (older versions of) Internet Explorer will accept round ones in all places.
Another solution is:
document.getElementById('elementId').selectedOptions[0].value
The simplest way to do this is:
var value = document.getElementById("selectId").value;
You can use querySelector.
E.g.
var myElement = document.getElementById('ddlViewBy');
var myValue = myElement.querySelector('[selected]').value;
Running example of how it works:
var e = document.getElementById("ddlViewBy");
var val1 = e.options[e.selectedIndex].value;
var txt = e.options[e.selectedIndex].text;
document.write("<br />Selected option Value: "+ val1);
document.write("<br />Selected option Text: "+ txt);
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2">test2</option>
<option value="3" selected="selected">test3</option>
</select>
Note: The values don't change as the dropdown is changed, if you require that functionality then an onClick change is to be implemented.
To go along with the previous answers, this is how I do it as a one-liner. This is for getting the actual text of the selected option. There are good examples for getting the index number already. (And for the text, I just wanted to show this way)
let selText = document.getElementById('elementId').options[document.getElementById('elementId').selectedIndex].text
In some rare instances you may need to use parentheses, but this would be very rare.
let selText = (document.getElementById('elementId')).options[(document.getElementById('elementId')).selectedIndex].text;
I doubt this processes any faster than the two line version. I simply like to consolidate my code as much as possible.
Unfortunately this still fetches the element twice, which is not ideal. A method that only grabs the element once would be more useful, but I have not figured that out yet, in regards to doing this with one line of code.
I have a bit different view of how to achieve this. I'm usually doing this with the following approach (it is an easier way and works with every browser as far as I know):
<select onChange="functionToCall(this.value);" id="ddlViewBy">
<option value="value1">Text one</option>
<option value="value2">Text two</option>
<option value="value3">Text three</option>
<option value="valueN">Text N</option>
</select>
In 2015, in Firefox, the following also works.
e.options.selectedIndex
In more modern browsers, querySelector allows us to retrieve the selected option in one statement, using the :checked pseudo-class. From the selected option, we can gather whatever information we need:
const opt = document.querySelector('#ddlViewBy option:checked');
// opt is now the selected option, so
console.log(opt.value, 'is the selected value');
console.log(opt.text, "is the selected option's text");
<select id="ddlViewBy">
<option value="1">test1</option>
<option value="2" selected="selected">test2</option>
<option value="3">test3</option>
</select>
event.target.value inside the onChange callback did the trick for me.
Most answers here get the value of the "this" select menu onchange by a plain text JavaScript selector.
For example:
document.getElementById("ddlViewBy").value;
This is not a DRY approach.
DRY (three lines of code):
function handleChange(e) {
let innerText = e.target[e.target.options.selectedIndex].innerText;
let value = e.target.value;
/* Do something with these values */
}
Get the first select option:
console.log(e.target[0]); /* Output: <option value="value_hello">Hello innerText</option>*/
With this idea in mind, we dynamically return a "this" select option item (by selectedIndex):
e.target[e.target.options.selectedIndex].innerText;
Demo
let log = document.getElementById('log');
function handleChange(e) {
let innerText = e.target[e.target.options.selectedIndex].innerText;
let value = e.target.value;
log.innerHTML = `<table>
<tr><th>value</th><th>innerText</th></tr>
<tr><td>${value}</td><td>${innerText}</td></tr>
</table>`;
}
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/milligram/1.4.1/milligram.css">
<select id="greet" onchange="handleChange(event)">
<option value="value_hello">Hello innerText</option>
<option value="value_goodbye">Goodbye innerText</option>
<option value="value_seeYou">See you... innerText</option>
</select>
<select id="other_select_menu" onchange="handleChange(event)">
<option value="value_paris">Paris innerText</option>
<option value="value_ny">New York innerText</option>
</select>
<div id="log"></div>
Here is a JavaScript code line:
var x = document.form1.list.value;
Assuming that the dropdown menu named list name="list" and included in a form with name attribute name="form1".
I think you can attach an event listener to the select tag itself e.g:
<script>
document.addEventListener("DOMContentLoaded", (_) => {
document.querySelector("select").addEventListener("change", (e) => {
console.log(e.target.value);
});
});
</script>
In this scenario, you should make sure you have a value attribute for all of your options, and they are not null.
You should be using querySelector to achieve this. This also standardizes the way of getting a value from form elements.
var dropDownValue = document.querySelector('#ddlViewBy').value;
Fiddle: https://jsfiddle.net/3t80pubr/
Try
ddlViewBy.value // value
ddlViewBy.selectedOptions[0].text // label
console.log( ddlViewBy.value );
console.log( ddlViewBy.selectedOptions[0].text );
<select id="ddlViewBy">
<option value="1">Happy</option>
<option value="2">Tree</option>
<option value="3" selected="selected">Friends</option>
</select>
Here's an easy way to do it in an onchange function:
event.target.options[event.target.selectedIndex].dataset.name
<select name="test" id="test" >
<option value="1" full-name="Apple">A</option>
<option value="2" full-name="Ball">B</option>
<option value="3" full-name="Cat" selected>C</option>
</select>
var obj = document.getElementById('test');
obj.options[obj.selectedIndex].value; //3
obj.options[obj.selectedIndex].text; //C
obj.options[obj.selectedIndex].getAttribute('full-name'); //Cat
obj.options[obj.selectedIndex].selected; //true
There is a workaround, using the EasyUI framework with all of its plugins.
You only need to add some EasyUI object that can read from an input as a "bridge" to the drop-down menu.
Example: easyui-searchbox
To the left, the drop-down, to the right, the easyui-searchbox:
...
<input id="ss" class="easyui-searchbox" style="width:300px"
data-options=" searcher:my_function,
prompt:'Enter value',
menu:'#mm'">
<div id="mm" style="width:200px">
<div data-options="name:'1'">test1</div>
<div data-options="name:'2'">test2</div>
</div>
...
...
<script type="text/javascript">
function my_js_function(triggeredByButton = false){
// normal text of the searchbox (what you entered)
var value = $("#ss").searchbox("getValue");
// what you chose from the drop-down menu
var name = $("#ss").searchbox("getName");
...
Mind: the var name is the '1' or '2', that is, the "value of the drop-down", while var value is the value that was entered in the easyui-searchbox instead and not relevant if you only want to know the value of the drop-down.
I checked how EasyUI fetches that #mm name, and I could not find out how to get that name without the help of EasyUI. The jQuery behind getName:
getName:function(jq){
return $.data(jq[0],"searchbox").searchbox.find("input.textbox-value").attr("name");
}
Mind that the return of this function is not the value of the easyui-searchbox, but the name of the #mm drop-down that was used as the menu parameter of the easyui-searchbox. Somehow EasyUI must get that other value, therefore it must be possible.
If you do not want any plugin to be seen, make it as tiny as possible? Or find perhaps a plugin that does not need a form at all in the link above, I just did not take the time.
My usage is simple, I have a simple select element on my page.
<select id="project-dropdown">
<option data-url="/constructions/6">Test 1</option>
<option data-url="/constructions/7">Test 2</option>
</select>
And in Javascript:
$('#project-dropdown').change(function() {
var url = $(this).find(':selected').data('url');
window.location = url;
});
This event works fine except when I want to go to the first option. The page starts out with the first element selected so I can't fire the changed event on it.
Any suggestions?
Does a little hack like this works for you?
HTML Part:
<select id="project-dropdown">
<option data-url="#">Select a value</option>
<option data-url="/constructions/6">Test 1</option>
<option data-url="/constructions/7">Test 2</option>
</select>
JS Part:
$('#project-dropdown').change(function() {
var url = $(this).find(':selected').data('url');
if(url !== "#")
window.location = url;
});
JsFiddle
Just call $('#project-dropdown').change(); after change binding. Like this:
$('#project-dropdown').change(function() {
var url = $(this).find(':selected').data('url');
window.location = url;
});
$('#project-dropdown').change();
Here is its JSFiddle.
I recommend you change your HTML to:
<select id="project-dropdown" size=2>
<option data-url="/constructions/6">Test 1</option>
<option data-url="/constructions/7">Test 2</option>
</select>
By setting size=2 you override the default value of 1, which causes the list to be displayed as a single line, with the initial option pre-selected (with the side-effect that clicking it does not trigger a change event).
Setting size to 2 or more causes the options to be displayed in a list that is size lines high, with no initial selections, so that the user can choose any of the options, including the first.
I have a relatively simple form which asks a variety of questions. One of those questions is answered via a Select Box. What I would like to do is if the person selects a particular option, they are prompted for more information.
With the help of a few online tutorials, I've managed to get the Javascript to display a hidden div just fine. My problem is I can't seem to localise the event to the Option tag, only the Select tag which is no use really.
At the moment the code looks like (code simplified to aid clarity!):
<select id="transfer_reason" name="transfer_reason onChange="javascript:showDiv('otherdetail');">
<option value="x">Reason 1</option>
<option value="y">Reason 2</option>
<option value="other">Other Reason</option>
</select>
<div id="otherdetail" style="display: none;">More Detail Here Please</div>
What I would like is if they choose "Other Reason" it then displays the div. Not sure how I achieve this if onChange can't be used with the Option tag!
Any assistance much appreciated :)
Note: Complete beginner when it comes to Javascript, I apologise if this is stupidly simple to achieve!
Setup the onchange event handler for the select box to look at the currently selected index. If the selected index is that of the 'Other Reason' option, then display the message; otherwise, hide the division.
<html>
<head>
<script type="text/javascript">
window.onload = function() {
var eSelect = document.getElementById('transfer_reason');
var optOtherReason = document.getElementById('otherdetail');
eSelect.onchange = function() {
if(eSelect.selectedIndex === 2) {
optOtherReason.style.display = 'block';
} else {
optOtherReason.style.display = 'none';
}
}
}
</script>
</head>
<body>
<select id="transfer_reason" name="transfer_reason">
<option value="x">Reason 1</option>
<option value="y">Reason 2</option>
<option value="other">Other Reason</option>
</select>
<div id="otherdetail" style="display: none;">More Detail Here Please</div>
</body>
</html>
Personally, I'd take it a step further and move the JavaScript into an external file and just include it in the header of the page; however, for all intents and purposes, this should help answer your question.
After reading Tom's great response, I realised that if I ever added other options to my form it would break. In my example this is quite likely, because the options can be added/deleted using a php admin panel.
I did a little reading and altered it ever so slightly so that rather than using selectedIndex it uses value instead.
<script type="text/javascript">
window.onload = function() {
var eSelect = document.getElementById('transfer_reason');
var optOtherReason = document.getElementById('otherdetail');
eSelect.onchange = function() {
if(eSelect.value === "Other") {
optOtherReason.style.display = 'block';
} else {
optOtherReason.style.display = 'none';
}
}
}
</script>
Hope this helps someone else in the future!
Tom's answer is elegant, and neatly puts the JS away from the HTML markup. As mentioned, it could be even moved to an external file. However it adds quite much "nonsense" to the code, like multiple anonymous function assignments etc.
If you want quick solution, you can put it all in the onchange() inside the select tag as well. Pick the one you see more fit.
<select id="transfer_reason" name="transfer_reason" onchange="document.getElementById('otherdetail').style.display = (this.selectedIndex === 2) ? 'block' : 'none';">
<option value="x">Reason 1</option>
<option value="y">Reason 2</option>
<option value="other">Other Reason</option>
</select>
<div id="otherdetail" style="display: none;">More Detail Here Please</div>