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Let's say I have an html form. Each input/select/textarea will have a corresponding <label>
with the for
attribute set to the id of it's companion. In this case, I know that each input will only have a single label.
Given an input element in javascript — via an onkeyup event, for example — what's the best way to find it's associated label?
Let's say I have an html form. Each input/select/textarea will have a corresponding <label>
with the for
attribute set to the id of it's companion. In this case, I know that each input will only have a single label.
Given an input element in javascript — via an onkeyup event, for example — what's the best way to find it's associated label?
Share Improve this question edited Apr 10, 2014 at 16:49 Joel Coehoorn asked Nov 12, 2008 at 21:55 Joel CoehoornJoel Coehoorn 415k114 gold badges577 silver badges813 bronze badges 3 |24 Answers
Reset to default 118If you are using jQuery you can do something like this
$('label[for="foo"]').hide ();
If you aren't using jQuery you'll have to search for the label. Here is a function that takes the element as an argument and returns the associated label
function findLableForControl(el) {
var idVal = el.id;
labels = document.getElementsByTagName('label');
for( var i = 0; i < labels.length; i++ ) {
if (labels[i].htmlFor == idVal)
return labels[i];
}
}
First, scan the page for labels, and assign a reference to the label from the actual form element:
var labels = document.getElementsByTagName('LABEL');
for (var i = 0; i < labels.length; i++) {
if (labels[i].htmlFor != '') {
var elem = document.getElementById(labels[i].htmlFor);
if (elem)
elem.label = labels[i];
}
}
Then, you can simply go:
document.getElementById('MyFormElem').label.innerHTML = 'Look ma this works!';
No need for a lookup array :)
There is a labels
property in the HTML5 standard which points to labels which are associated to an input element.
So you could use something like this (support for native labels
property but with a fallback for retrieving labels in case the browser doesn't support it)...
var getLabelsForInputElement = function(element) {
var labels = [];
var id = element.id;
if (element.labels) {
return element.labels;
}
id && Array.prototype.push
.apply(labels, document.querySelector("label[for='" + id + "']"));
while (element = element.parentNode) {
if (element.tagName.toLowerCase() == "label") {
labels.push(element);
}
}
return labels;
};
// ES6
var getLabelsForInputElement = (element) => {
let labels;
let id = element.id;
if (element.labels) {
return element.labels;
}
if (id) {
labels = Array.from(document.querySelector(`label[for='${id}']`)));
}
while (element = element.parentNode) {
if (element.tagName.toLowerCase() == "label") {
labels.push(element);
}
}
return labels;
};
Even easier if you're using jQuery...
var getLabelsForInputElement = function(element) {
var labels = $();
var id = element.id;
if (element.labels) {
return element.labels;
}
id && (labels = $("label[for='" + id + "']")));
labels = labels.add($(element).parents("label"));
return labels;
};
This answers the question in the simplest and leanest manner.
document.querySelector("label[for=" + vHtmlInputElement.id + "]");
This uses vanilla javascript and works on all main-stream proper browsers.
I am a bit surprised that nobody seems to know that you're perfectly allowed to do:
<label>Put your stuff here: <input value="Stuff"></label>
Which won't get picked up by any of the suggested answers, but will label the input correctly.
Here's some code that does take this case into account:
$.fn.getLabels = function() {
return this.map(function() {
var labels = $(this).parents('label');
if (this.id) {
labels.add('label[for="' + this.id + '"]');
}
return labels.get();
});
};
Usage:
$('#myfancyinput').getLabels();
Some notes:
- The code was written for clarity, not for performance. More performant alternatives may be available.
- This code supports getting the labels of multiple items in one go. If that's not what you want, adapt as necessary.
- This still doesn't take care of things like
aria-labelledby
if you were to use that (left as an exercise to the reader). - Using multiple labels is a tricky business when it comes to support in different user agents and assistive technologies, so test well and use at your own risk, etc. etc.
- Yes, you could also implement this without using jQuery. :-)
All the other answers are extremely outdated!!
All you have to do is:
input.labels
HTML5 has been supported by all of the major browsers for many years already. There is absolutely no reason that you should have to make this from scratch on your own or polyfill it! Literally just use input.labels
and it solves all of your problems.
Earlier...
var labels = document.getElementsByTagName("LABEL"),
lookup = {},
i, label;
for (i = 0; i < labels.length; i++) {
label = labels[i];
if (document.getElementById(label.htmlFor)) {
lookup[label.htmlFor] = label;
}
}
Later...
var myLabel = lookup[myInput.id];
Snarky comment: Yes, you can also do it with JQuery. :-)
with jquery you could do something like
var nameOfLabel = someInput.attr('id');
var label = $("label[for='" + nameOfLabel + "']");
If you're willing to use querySelector (and you can, even down to IE9 and sometimes IE8!), another method becomes viable.
If your form field has an ID, and you use the label's for
attribute, this becomes pretty simple in modern JavaScript:
var form = document.querySelector('.sample-form');
var formFields = form.querySelectorAll('.form-field');
[].forEach.call(formFields, function (formField) {
var inputId = formField.id;
var label = form.querySelector('label[for=' + inputId + ']');
console.log(label.textContent);
});
Some have noted about multiple labels; if they all use the same value for the for
attribute, just use querySelectorAll
instead of querySelector
and loop through to get everything you need.
A really concise solution using ES6 features like destructuring and implicit returns to turn it into a handy one liner would be:
const getLabels = ({ labels, id }) => labels || document.querySelectorAll(`label[for=${id}]`)
Or to simply get one label, not a NodeList:
const getFirstLabel = ({ labels, id }) => labels && labels[0] || document.querySelector(`label[for=${id}]`)
Solution One <label>
: One <input>
Using HTML 5.2 reference
Considering the <label>
pointing to <input>
using for=
, the labels element will be a non empty array, and act as a link to the <label>
element, accessing all properties of it, including its id=
.
function myFunction() {
document.getElementById("p1").innerHTML = "The first label associated with input: <b>" + document.getElementById("input4").labels[0].id + "</b>";
}
<form>
<label id="theLabel" for="input4">my id is "theLabel"</label>
<input name="name1" id="input4" value="my id is input4">
<br>
</form>
<p>Click the "click me" button to see the label properties</p>
<button onclick="myFunction()">click me</button>
<p id="p1"></p>
Solution Many <label>
: One <input>
With more than one <label>
using for=
, you can make a loop to show all of them, like this:
function myFunction2() {
var x = document.getElementById("input7").labels;
let text = "";
for (let i = 0; i < x.length; i++) {
text += x[i].id + "<br>";
}
document.getElementById("p7").innerHTML = text;
}
<b>Three labels for one input</b><br>
<br>
<form>
<label id="theLabel2" for="input7">my id is "theLabel2</label><br>
<label id="theLabel3" for="input7">my id is "theLabel3</label><br>
<label id="theLabel4" for="input7">my id is "theLabel4</label><br>
<input name="name1" id="input7" value="my id is input7">
<br>
</form>
<p>Click the "click me" button to see the label properties</p>
<button onclick="myFunction2()">click me2</button>
<p id="p7"></p>
$("label[for='inputId']").text()
This helped me to get the label of an input element using its ID.
Answer from Gijs was most valuable for me, but unfortunately the extension does not work.
Here's a rewritten extension that works, it may help someone:
jQuery.fn.getLabels = function () {
return this.map(function () {
var parentLabels = $(this).parents('label').get();
var associatedLabels = this.id ? associatedLabels = $("label[for='" + this.id + "']").get() : [];
return parentLabels.concat(associatedLabels);
});
};
As it has been already mentionned, the (currently) top-rated answer does not take into account the possibility to embed an input inside a label.
Since nobody has posted a JQuery-free answer, here is mine :
var labels = form.getElementsByTagName ('label');
var input_label = {};
for (var i = 0 ; i != labels.length ; i++)
{
var label = labels[i];
var input = label.htmlFor
? document.getElementById(label.htmlFor)
: label.getElementsByTagName('input')[0];
input_label[input.outerHTML] =
(label.innerText || label.textContent); // innerText for IE8-
}
In this example, for the sake of simplicity, the lookup table is directly indexed by the input HTML elements. This is hardly efficient and you can adapt it however you like.
You can use a form as base element, or the whole document if you want to get labels for multiple forms at once.
No checks are made for incorrect HTML (multiple or missing inputs inside labels, missing input with corresponding htmlFor id, etc), but feel free to add them.
You might want to trim the label texts, since trailing spaces are often present when the input is embedded in the label.
The best answer works perfectly fine but in most cases, it is overkill and inefficient to loop through all the label
elements.
Here is an efficent function to get the label
that goes with the input
element:
function getLabelForInput(id)
{
var el = document.getElementById(id);
if (!el)
return null;
var elPrev = el.previousElementSibling;
var elNext = el.nextElementSibling;
while (elPrev || elNext)
{
if (elPrev)
{
if (elPrev.htmlFor === id)
return elPrev;
elPrev = elPrev.previousElementSibling;
}
if (elNext)
{
if (elNext.htmlFor === id)
return elNext;
elNext = elNext.nextElementSibling;
}
}
return null;
}
For me, this one line of code was sufficient:
el = document.getElementById(id).previousElementSibling;
In most cases, the label
will be very close or next to the input, which means the loop in the above function only needs to iterate a very small number of times.
It is actually far easier to add an id to the label in the form itself, for example:
<label for="firstName" id="firstNameLabel">FirstName:</label>
<input type="text" id="firstName" name="firstName" class="input_Field"
pattern="^[a-zA-Z\s\-]{2,25}$" maxlength="25"
title="Alphabetic, Space, Dash Only, 2-25 Characters Long"
autocomplete="on" required
/>
Then, you can simply use something like this:
if (myvariableforpagelang == 'es') {
// set field label to spanish
document.getElementById("firstNameLabel").innerHTML = "Primer Nombre:";
// set field tooltip (title to spanish
document.getElementById("firstName").title = "Alfabética, espacio, guión Sólo, 2-25 caracteres de longitud";
}
The javascript does have to be in a body onload
function to work.
I have made for my own need, can be useful for somebody: JSFIDDLE
$("input").each(function () {
if ($.trim($(this).prev('label').text()) != "") {
console.log("\nprev>children:");
console.log($.trim($(this).prev('label').text()));
} else {
if ($.trim($(this).parent('label').text()) != "") {
console.log("\nparent>children:");
console.log($.trim($(this).parent('label').text()));
} else {
if ($.trim($(this).parent().prev('label').text()) != "") {
console.log("\nparent>prev>children:");
console.log($.trim($(this).parent().prev('label').text()));
} else {
console.log("NOTFOUND! So set your own condition now");
}
}
}
});
I am bit surprised no one is suggesting to use the CSS relationship method?
in a style sheet you can reference a label from the element selector:
<style>
//for input element with class 'YYY'
input.YYY + label {}
</style>
if the checkbox has an id of 'XXX' then the label would be found through jQuery by:
$('#XXX + label');
You can also apply .find('+ label') to return the label from a jQuery checkbox element, ie useful when looping:
$('input[type=checkbox]').each( function(){
$(this).find('+ label');
});
If you use the for
attribute, you can use querySelector(...) to get
the associated label.
HTML/JavaScript
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
</head>
<body>
<label for="myCheckbox">Log Report to Console?</label>
<input name="myCheckbox" type="checkbox" oninput="doSomething(event)" />
<script type="text/javascript">
function doSomething(e) {
const query = `label[for="${e.target.name}"]`; // This is string interpolation NOT JQuery
const label = document.querySelector(query);
}
</script>
</body>
</html>
Plain JavaScript
function doSomething(e) {
// const query = `label[for="${e.target.name}"]`; // This is string interpolation NOT JQuery
// Maybe it is safer to use ".getAttribute"
const query = `label[for="${e.target.getAttribute("name")}"]`;
const label = document.querySelector(query);
// Do what you want with the label here...
debugger; // You're welcome
console.log(label);
}
A more modern way:
function replaceLabel(name) {
Array.from(document.getElementsByTagName('label'))
.filter(l => l.htmlFor=name)
.forEach(l => l.textContent = "New Label Name");
}
<label for="user">Old Label Name</label>
<input name="user"></input>
<button onclick="replaceLabel('user')">replace</button>
The only caveat is, that should you have multiple labels for the same input (which would be odd) they would all get replaced. If only like to change the first label with the matching name add .slice(0, 1)
inbetween the filter and the forEach-method calls.
jQueryUI has a labels()
function:
input.labels()
, basically does what $('label[for="name"]')
does.
You can find more information on the documentation
I know this is old, but I had trouble with some solutions and pieced this together. I have tested this on Windows (Chrome, Firefox and MSIE) and OS X (Chrome and Safari) and believe this is the simplest solution. It works with these three style of attaching a label.
<label><input type="checkbox" class="c123" id="cb1" name="item1">item1</label>
<input type="checkbox" class="c123" id="cb2" name="item2">item2</input>
<input type="checkbox" class="c123" id="cb3" name="item3"><label for="cb3">item3</label>
Using jQuery:
$(".c123").click(function() {
$cb = $(this);
$lb = $(this).parent();
alert( $cb.attr('id') + ' = ' + $lb.text() );
});
My JSFiddle: http://jsfiddle.net/pnosko/6PQCw/
Use a JQuery selector:
$("label[for="+inputElement.id+"]")
For future searchers... The following is a jQuery-ified version of FlySwat's accepted answer:
var labels = $("label");
for (var i = 0; i < labels.length; i++) {
var fieldId = labels[i].htmlFor;
if (fieldId != "") {
var elem = $("#" + fieldId);
if (elem.length != 0) {
elem.data("label", $(labels[i]));
}
}
}
Using:
$("#myFormElemId").data("label").css("border","3px solid red");
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function getInputLabel(thisElement) { var theAssociatedLabel,elementID; elementID = thisElement.id; theAssociatedLabel = thisElement.parentNode.querySelector("label[for='" + elementID + "']"); console.log('theAssociatedLabel.htmlFor: ' + theAssociatedLabel.htmlFor); theAssociatedLabel.style.backgroundColor = "green";//Set the label background color to green };
– Alan Wells Commented Oct 28, 2016 at 3:02