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Sets or retrieves the prefix of the fully qualified XML declaration for a node.

Property of dom/Nodedom/Node


Note: This property is read-only.

var prefix = node.prefix;

Return Value

Returns an object of type StringString

The prefix portion of the qualified name of the node.


This example will only work when a namespace-aware parser is used, i.e. when a document is served with an XML mime-type. This will not work for HTML documents.

<x:div onclick="alert(this.prefix)"/>


 In XML documents, elements can be declared using qualified names, which consist of a prefix and a localName. This property returns the former value.

For more information, see W3C Namespaces in XML.


Prior to Gecko 5.0 (Firefox 5.0 / Thunderbird 5.0 / SeaMonkey 2.2), this property was read-write; the specification says it should be read only, and now it is.

Related specifications

DOM Level 3 Core