当前位置：文江博客知识库 en-US 文档 Web API Element hasAttributeNS

Element.hasAttributeNS() - Web APIs 编辑

hasAttributeNS returns a boolean value indicating whether the current element has the specified attribute.

Syntax

result = element.hasAttributeNS(namespace,localName)

result is the boolean value true or false.
namespace is a string specifying the namespace of the attribute.
localName is the name of the attribute.

Example

// Check that the attribute exists before you set a value
var d = document.getElementById("div1");
if (d.hasAttributeNS(
       "http://www.mozilla.org/ns/specialspace/",
       "special-align")) {
  d.setAttribute("align", "center");
}

Notes

DOM methods dealing with element's attributes:

Not namespace-aware, most commonly used methods	Namespace-aware variants (DOM Level 2)	DOM Level 1 methods for dealing with `Attr` nodes directly (seldom used)	DOM Level 2 namespace-aware methods for dealing with `Attr` nodes directly (seldom used)
`setAttribute` (DOM 1)	`setAttributeNS`	`setAttributeNode`	`setAttributeNodeNS`
`getAttribute` (DOM 1)	`getAttributeNS`	`getAttributeNode`	`getAttributeNodeNS`
`hasAttribute` (DOM 2)	`hasAttributeNS`	-	-
`removeAttribute` (DOM 1)	`removeAttributeNS`	`removeAttributeNode`	-