jQuery is() Method
The is() method in jQuery is used to find out whether the selected elements match a specified selector, element, or jQuery object.
This method returns a Boolean value: "true" if at least one of the selected elements matches the specified criteria; "false" if none of the selected elements matches the specified criteria.
Syntax
Following is the syntax of the is() method in jQuery −
$(selector).is(selectorElement,function(index,element))
Parameters
This method accepts the following parameters −
- selectorElement: A selector, element, or jQuery object used to match against the selected elements.
- function(index, element): It specifies a function to run for the group of selected elements.
Example 1
The following example uses the is() method to check if a paragraph element is visible and changes its background color accordingly −
<html>
<head>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
<script>
$(document).ready(function(){
$('button').click(function(){
if ($('p').is(':visible')) {
$('p').css('background-color', 'green');
} else {
alert("Paragraph is hidden");
}
});
});
</script>
</head>
<body>
<!--Paragraph is hidden-->
<p style="display: none;">This is a hidden paragraph.</p>
<button>Check Visibility</button>
</body>
</html>
When we click the button, it gives an alert saying that "Paragraph is hidden" because the <p> is defined as "display:none".
Example 2
In this example, we are checking if the specified element ("a") is an Anchor Tag −
<html>
<head>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
<script>
$(document).ready(function(){
$('a').click(function(){
if ($(this).is('a')) {
alert('Clicked element is an anchor tag.');
} else {
alert('Clicked element is not an anchor tag.');
}
});
});
</script>
</head>
<body>
<a href="#">Click me to verify</a>
</body>
</html>
When we click the button, it gives an alert saying that "Clicked element is an anchor tag" because the element we are checking is an anchor tag.
Example 3
In this example below, we are using the parent() and is() methods to find out if "ul" is the parent of "li" element −
<html>
<head>
<script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
<script>
$(document).ready(function(){
$('li').click(function(){
if ($(this).parent().is('ul')) {
alert('Parent of li is ul.');
} else {
alert('Parent of li is NOT ul.');
}
});
});
</script>
</head>
<body>
<div>
<ul>
<li>Click me to verify if my parent is ul element.</li>
</ul>
</div>
</body>
</html>
After clicking on the button, it gives an alert saying "Parent of li is ul" because the element "li" is a descendant of "ul" element.