What's the purpose of the for attribute in HTML? - html

I understand the for attribute specifies which form element a label is bound to.
Do you have an example where this would be actually useful?

It's most useful for a checkbox label where it will make the whole label clickable so you don't have to target the checkbox itself to toggle its state. Same for radio buttons.

<label for="email">E-mail:</label>
<input type="text" id="email" name="email"/>
Now if you click on "E-mail", the corresponding input element will get focused.

<label for="name">Name</label>
<input type="text" id="name" />
http://jsfiddle.net/jRB2s/3/
Clicking on the label will give focus to the element with the same ID as the for value.
For radio buttons or checkboxes, it will toggle their status as if you were clicking on them.
This is really useful expecially on handheld devices, where it's not always simple to click the desired form control.

It's there for semantic purposes. It's useful for screen readers and such as well as, potentially, search engines. Browsers will also connect controls to their labels (e.g. checkboxes will activate when clicking a label) and you can apply shortcut keys to labels which will focus their controls when pressed.
There are two formats for labels:
<label>Label<input ... /></label>
which doesn't require a for attribute. And
<label for="control">Label</label>
<input id="control" name="control" ... />
which may be required when the label and input are separated (e.g. a table).

Related

HTML - Meaning of "for" attribute of label tag [duplicate]

You can label an input field with a <label> tag like this:
<label for="username">Username:</label>
<input id="username" name="username" type="text">
But why?
Is it effective for SEO? Or browser rendering? Or better support for mobile or other devices?
The label tag supports with a click the focus on the input element where id attribute equals labels for attribute.
If you have e.g. a checkbox you can choose this one also with a click on the label.
Example:
<input type="checkbox" value="1" id="myCheckbox"/>
// A click here set the focus on the according checkbox without javascript things
// And it's easier to select than a small checkbox element
<label for="myCheckbox">My Checkbox</label>
The primary benefits are:
Accessibility - it lets screen readers know which form control the text applies to, this lets them accurately tell the user what they are expected to enter in a field
Click targets - clicking on the label has the same effect as clicking on the form control, larger click targets are easier to hit, especially when the input is as small as a radio button

When a label only has a button, a button click does not (fully?) trigger the label

I have two inputs of type radio. For each input there's a correspoding label with a single button inside.
I was expecting that clicking the button would have the same effect as clicking the label: that the corresponding input would be checked.
However, this does not happen. As shown by the following snippet, hovering and pressing the buttons does trigger the corresponding style changes in the radio buttons, but the click action does not select the input, even though the simple labels work as expected.
I've checked that buttons are legal children of labels. Labels allow Phrasing Content, and buttons are Phrasing Content, so everything should be okay there.
I have also tried to add an event listener to both buttons' click events, and within them calling event.preventDefault(), just to make sure that the default behaviour of the button was not preventing the event from bubbling up to the label, but to no avail, the label is receiving the event.
Since this seems to be consistent across browsers (Tested on Firefox 41a and Opera 31b / Chrome 44):
What's happening here that I'm missing?
How can I implement this without trickery (such as styling the label as if it were a button)?
<div>
<input type="radio" name="A" id="one" />
<label for="one">One</label>
<label for="one">
<button type="button">One</button>
</label>
<input type="radio" name="A" id="two" />
<label for="two">Two</label>
<label for="two">
<button type="button">Two</button>
</label>
</div>
A label can only be associated with one form control at a time. This is evidenced by the fact that the for attribute points to an element with a matching ID attribute.
You have a button that is a descendant of your label; the expected interpretation of this is that the label serves as a label for the button. However, you're trying to associate the radio button, not the button element, with the label. The real problem here is that there is a conflict between the form controls and the label; it's unable to figure out which control it's supposed to be associated to.
I'm guessing that the fact the radio button isn't working correctly is a side effect of this. Perhaps it's down to some activation behavior in both the radio button and the button element.
I've checked that buttons are legal children of labels. Labels allow Phrasing Content, and buttons are Phrasing Content, so everything should be okay there.
The validator does nevertheless produce the following error with your markup:
Error: Any button descendant of a label element with a for attribute must have an ID value that matches that for attribute.
This is because a label element with a for attribute needs to have a form control with that ID value for the for attribute to point to, even if that control is a descendant of the label itself. But you can't assign the same ID to more than one element. The result is the aforementioned conflict.
Without knowing what you're trying to accomplish here, the best advice I can give if you just want the label to have the appearance of a button is to just style it as such.
<div>
<input type="radio" name="A" id="one" />
<label for="one">One</label>
<label for="one">
<span style="color: red;">One</span>
</label>
<input type="radio" name="A" id="two" />
<label for="two">Two</label>
<label for="two">
<span style="color: blue;">Two</span>
</label>
</div>

Why should you use the <label> tag and 'for' attribute?

You can label an input field with a <label> tag like this:
<label for="username">Username:</label>
<input id="username" name="username" type="text">
But why?
Is it effective for SEO? Or browser rendering? Or better support for mobile or other devices?
The label tag supports with a click the focus on the input element where id attribute equals labels for attribute.
If you have e.g. a checkbox you can choose this one also with a click on the label.
Example:
<input type="checkbox" value="1" id="myCheckbox"/>
// A click here set the focus on the according checkbox without javascript things
// And it's easier to select than a small checkbox element
<label for="myCheckbox">My Checkbox</label>
The primary benefits are:
Accessibility - it lets screen readers know which form control the text applies to, this lets them accurately tell the user what they are expected to enter in a field
Click targets - clicking on the label has the same effect as clicking on the form control, larger click targets are easier to hit, especially when the input is as small as a radio button

What is the HTML for="" attribute in <label>?

I have seen this in jQuery - what does it do?
<label for="name"> text </label>
<input type="text" name="name" value=""/>
The for attribute is used in labels. It refers to the id of the element this label is associated with.
For example:
<label for="username">Username</label>
<input type="text" id="username" name="username" />
Now when the user clicks with the mouse on the username text the browser will automatically put the focus in the corresponding input field. This also works with other input elements such as <textbox> and <select>.
Quote from the specification:
This attribute explicitly associates the label being defined with
another control. When present, the value of this attribute must be the
same as the value of the id attribute of some other control in the
same document. When absent, the label being defined is associated with
the element's contents.
As far as why your question is tagged with jQuery and where did you see it being used in jQuery I cannot answer because you didn't provide much information.
Maybe it was used in a jQuery selector to find the corresponding input element given a label instance:
var label = $('label');
label.each(function() {
// get the corresponding input element of the label:
var input = $('#' + $(this).attr('for'));
});
To associate the <label> with an <input> element, you need to give the <input> an id attribute. The <label> then needs a for attribute whose value is the same as the input's id:
<label for="username">Click me</label>
<input type="text" id="username">
The for attribute associates a <label> with an <input> element; which offers some major advantages:
1. The label text is not only visually associated with its corresponding text input; it is programmatically associated with it too. This means that, for example, a screen reader will read out the label when the user is focused on the form input, making it easier for an assistive technology user to understand what data should be entered.
2. You can click the associated label to focus/activate the input, as well as the input itself. This increased hit area provides an advantage to anyone trying to activate the input, including those using a touch-screen device.
Alternatively, you can nest the <input> directly inside the <label>, in which case the for and id attributes are not needed because the association is implicit:
<label>Click me <input type="text"></label>
Notes:
One input can be associated with multiple labels.
When a <label> is clicked or tapped and it is associated with a form control, the resulting click event is also raised for the associated control.
Accessibility concerns
Don't place interactive elements such as anchors or buttons inside a label. Doing so, makes it difficult for people to activate the form input associated with the label.
Headings
Placing heading elements within a <label> interferes with many kinds of assistive technology, because headings are commonly used as a navigation aid. If the label's text needs to be adjusted visually, use CSS classes applied to the <label> element instead.
If a form, or a section of a form needs a title, use the <legend> element placed within a <fieldset>.
Buttons
An <input> element with a type="button" declaration and a valid value attribute does not need a label associated with it. Doing so may actually interfere with how assistive technology parses the button input. The same applies for the <button> element.
Ref:
https://developer.mozilla.org/en-US/docs/Web/HTML/Element/label
I feel the need to answer this. I had the same confusion.
<p>Click on one of the text labels to toggle the related control:</p>
<form action="/action_page.php">
<label for="female">Male</label>
<input type="radio" name="gender" id="male" value="male"><br>
<label for="female">Female</label>
<input type="radio" name="gender" id="female" value="female"><br>
<label for="other">Other</label>
<input type="radio" name="gender" id="other" value="other"><br><br>
<input type="submit" value="Submit">
</form>
I changed the for attribute on the 'male' label to female. Now, if you click 'male' the 'female' radio will get checked.
Simple as that.
a fast example:
<label for="name">Name:</label>
<input id="name" type="text" />
the for="" tag let focus the input when you click the label as well.
You use it with labels to say that two objects belong together.
<input type="checkbox" name="remember" id="rememberbox"/>
<label for="rememberbox">Remember your details?</label>
This also means that clicking on that label will change the value of the checkbox.
FYI - if you are in an typescript environment with e.g.
<label for={this.props.inputId}>{this.props.label}</label>
you need to use htmlFor
<label htmlFor={this.props.inputId}>{this.props.label}</label>
it is used for <label> element
it is used with input type checkbox or redio to select on label click
working demo
The for attribute of the <label> tag should be equal to the id attribute of the related element to bind them together.
It associates the label with an input element. HTML tags are meant to convey special meaning to users of various categories. Here is what label is meant for:
For people with motor disabilities (also for general mouse users): Correctly used label tags can be clicked to access the associated form control. Eg. Instead of particularly clicking the checkbox, user can click on more easily clickable label and toggle the checkbox.
For visually-challenged users: Visually challenged users use screen-readers that reads the associated label tag whenever a form control is focused. It helps users to know the label which was otherwise invisible to them.
More about labelling -> https://www.w3.org/TR/WCAG20-TECHS/H44.html
it is used in <label> text for html
eg.
<label for="male">Male</label>
<input type="radio" name="sex" id="male" value="male"><br>
It's the attribute for <label> tag : http://www.w3schools.com/tags/tag_label.asp

Two input fields inside one label

Consider the following:
<label>Range from
<input name='min_value'/> to
<input name='max_value' />
</label>
Is this semantically correct since the W3C recommendations state that a label is associated with exactly one form control?
Clicking into the second input shifts focus immediately to the first input? Can this be prevented?
How would one markup a min/max input combination to show that two inputs belong together?
No, it's not correct (since, as you note, a label is associated with exactly one form input).
To label a group of inputs that belong together, use a <fieldset> and a <legend>:
<fieldset>
<legend>Range</legend>
<label for="min">Min</label>
<input id="min" name="min" />
<label for="max">Max</label>
<input id="max" name="max" />
</fieldset>
References:
<input />HTML 5 spec.
<fieldset>HTML 5 spec.
<label>HTML 5 spec.
<legend>HTML 5 spec.
As the accepted answer states, that's not correct, however I think there are better ways to do it.
Accessible alternatives:
Option 1 (using the aria-label attribute):
Range:
<input ... aria-label='Range start' />
<input ... aria-label='Range end' />
Option 2 (using hidden label tags):
<label for='start'>Range start</label>
<input type='text' id='start' />
<label for='end' class='hidden'>Range end</label>
<input type='text' id='end' />
Where the .hidden class is only readable by screen readers.
Option 3 (using aria-labelledby attributes):
<label id='lblRange'>Range</label>
<input type='text' id='start' aria-labelledby='lblRange' />
<input type='text' id='end' aria-labelledby='lblRange' />
Advantages of option #1: Each input has a good description that other suggestions (such adding a "to" label) do not. Options #2 and #3 might not be the best for this specific case, but worth mentioning for similar cases.
Source: http://webaim.org/techniques/forms/advanced
I see many answers saying it is wrong to put 2 inputs inside a label.
This is actually a wrong statement in html5. The standard explicitly allow it:
http://www.w3.org/TR/html5/forms.html#the-label-element
If the for attribute is not specified, but the label element has a labelable element descendant, then the first such descendant in tree order is the label element’s labeled control.
If a label element has interactive content other than its labeled control, the activation behavior of the label element for events targeted at those interactive content descendants and any descendants of those must be to do nothing.
However, Safari does not respect the html5 standard here (tested on iOS 11.3). So, someone that wants to be compatible with Safari must use workarounds here or wait until Apple fixes its browser.
According to this - label can contain only one input as it should be associated with only one control. Putting input inside the label means elimination of for attribute (automatic linking).
So you should either put single input into label or specify for attribute which points to input id and don't put input into label.
How about this:
<label> Range from <input name='min_value'> </label>
<label> to <input name='max_value'> </label>
1 LABEL = 1 INPUT !!!
If you put 2 INPUTS inside a LABEL, it will NOT work in Safari (and iPad and iPhone)... because when you click inside LABEL it automatically focuses the first INPUT... so the second input is impossible to type to.
I see many answers saying it is wrong to put 2 inputs inside a label. This is actually a wrong statement in html5. The standard explicitly allow it: http://www.w3.org/TR/html5/forms.html#the-label-element
<label id='dobRange'>DOB between</label>
<input type='text' id='start' aria-labelledby='dobRange' />
<input type='text' id='end' aria-labelledby='dobRange' />
in haml:
= f.label :dob_range
= f.search_field :dob_gteq, 'aria-label': 'dob_range'
= f.search_field :dob_lteq, 'aria-label': 'dob_range'
i don't think you should be putting the input field inside the label control.
<label for="myfield">test</label><input type="text" id="myfield" name="myfield />
the label is just that, a label for something.