The HTML DOM isDefaultNamespace() method returns a boolean value (true/false) if specified namespace is default or not.
Note − An element node inherits the namespace of its parent node, therefore, all elements in an XHTML document has the namespaceURI "https://www.w3.org/1999/xhtml".
Syntax
Following is the syntax −
Calling isDefaultNamespace()
document.documentElement.isDefaultNamespace("nameSpaceURI")Example
Let us see an example for isDefaultNamespace() method −
<!DOCTYPE html>
<html>
<head>
<title>isDefaultNamespace()</title>
<style>
form {
width:70%;
margin: 0 auto;
text-align: center;
}
* {
padding: 2px;
margin:5px;
}
input[type="button"] {
border-radius: 10px;
}
</style>
</head>
<body>
<form>
<fieldset>
<legend>isDefaultNamespace( )</legend>
<label for="textSelect">URI:
<input type="url" size="25" id="textSelect" placeholder="https://www.abc.com">
</label><br>
<input type="button" onclick="confirmNameSpace()" value="Check">
<div id="divDisplay"></div>
</fieldset>
</form>
<script>
var divDisplay = document.getElementById("divDisplay");
var inputText = document.getElementById("textSelect");
divDisplay.textContent = 'NOTE: Check if specified URI is DefaultNamespace';
function confirmNameSpace() {
if(document.documentElement.isDefaultNamespace(textSelect.value))
divDisplay.textContent = 'Above given namespace is default';
else
divDisplay.textContent = 'Above given namespace is not default';
}
</script>
</body>
</html>Output
This will produce the following output −
Before clicking ‘Check’ button −
After clicking ‘Check’ button with invalid input −
After clicking ‘Check’ button with valid input −
