aboutsummaryrefslogtreecommitdiff
path: root/files/ar/web/api/node/index.html
blob: 25375da985c104dc677fa104d9b1b2d929a0a786 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
---
title: Node
slug: Web/API/Node
tags:
  - API
  - DOM
  - Interface
  - NeedsTranslation
  - Node
  - Reference
  - TopicStub
translation_of: Web/API/Node
---
<p>{{APIRef("DOM")}}</p>

<p><span class="seoSummary">The {{Glossary("DOM")}} <strong><code>Node</code></strong> interface is a key base class upon which many other DOM API objects are based, thus letting those object types to be used similarly and often interchangeably.</span> Key among the interfaces which inherit the features of <code>Node</code> are {{domxref("Document")}} and {{domxref("Element")}}. However, all of the following also inherit methods and properties from <code>Node</code>{{DOMxRef("Attr")}}, {{DOMxRef("CharacterData")}} (which {{DOMxRef("Text")}}, {{DOMxRef("Comment")}}, and {{DOMxRef("CDATASection")}} are all based on), {{DOMxRef("ProcessingInstruction")}}, {{DOMxRef("DocumentFragment")}}, {{DOMxRef("DocumentType")}}, {{DOMxRef("Notation")}}, {{DOMxRef("Entity")}}, and {{DOMxRef("EntityReference")}}.</p>

<p>In some cases, a particular feature of <code>Node</code> may not apply to a particular interface based on it; in that case, the inheriting node may return <code>null</code> or throw an exception, depending on circumstances. For example, attempting to add children to a node type that cannot have children will throw an exception.</p>

<p>{{InheritanceDiagram}}</p>

<h2 id="Properties">Properties</h2>

<p><em>Inherits properties from its parent, {{DOMxRef("EventTarget")}}</em>.<sup>[1]</sup></p>

<dl>
 <dt>{{DOMxRef("Node.baseURI")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("DOMString")}} representing the base URL of the document containing the <code>Node</code>.</dd>
 <dt>{{DOMxRef("Node.baseURIObject")}} {{Non-standard_inline}} {{ReadOnlyInline}}{{Fx_MinVersion_Inline("3")}}</dt>
 <dd>(Not available to web content.) The {{ Interface("nsIURI") }} object representing the base URI for the element.</dd>
 <dt>{{DOMxRef("Node.childNodes")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a live {{DOMxRef("NodeList")}} containing all the children of this node. {{DOMxRef("NodeList")}} being live means that if the children of the <code>Node</code> change, the {{DOMxRef("NodeList")}} object is automatically updated.</dd>
 <dt>{{DOMxRef("Node.firstChild")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("Node")}} representing the first direct child node of the node, or <code>null</code> if the node has no child.</dd>
 <dt>{{DOMxRef("Node.isConnected")}}{{ReadOnlyInline}}</dt>
 <dd>A boolean indicating whether or not the Node is connected (directly or indirectly) to the context object, e.g. the {{DOMxRef("Document")}} object in the case of the normal DOM, or the {{DOMxRef("ShadowRoot")}} in the case of a shadow DOM.</dd>
 <dt>{{DOMxRef("Node.lastChild")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("Node")}} representing the last direct child node of the node, or <code>null</code> if the node has no child.</dd>
 <dt>{{DOMxRef("Node.nextSibling")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("Node")}} representing the next node in the tree, or <code>null</code> if there isn't such node.</dd>
 <dt>{{DOMxRef("Node.nodeName")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("DOMString")}} containing the name of the <code>Node</code>. The structure of the name will differ with the node type. E.g. An {{DOMxRef("HTMLElement")}} will contain the name of the corresponding tag, like <code>'audio'</code> for an {{DOMxRef("HTMLAudioElement")}}, a {{DOMxRef("Text")}} node will have the <code>'#text'</code> string, or a {{DOMxRef("Document")}} node will have the <code>'#document'</code> string.</dd>
 <dt>{{DOMxRef("Node.nodeType")}}{{ReadOnlyInline}}</dt>
 <dd>Returns an <code>unsigned short</code> representing the type of the node. Possible values are:
 <table class="standard-table">
  <thead>
   <tr>
    <th scope="col">Name</th>
    <th scope="col">Value</th>
   </tr>
  </thead>
  <tbody>
   <tr>
    <td><code>ELEMENT_NODE</code></td>
    <td><code>1</code></td>
   </tr>
   <tr>
    <td><code>ATTRIBUTE_NODE</code> {{Deprecated_Inline}}</td>
    <td><code>2</code></td>
   </tr>
   <tr>
    <td><code>TEXT_NODE</code></td>
    <td><code>3</code></td>
   </tr>
   <tr>
    <td><code>CDATA_SECTION_NODE</code></td>
    <td><code>4</code></td>
   </tr>
   <tr>
    <td><code>ENTITY_REFERENCE_NODE</code> {{Deprecated_Inline}}</td>
    <td><code>5</code></td>
   </tr>
   <tr>
    <td><code>ENTITY_NODE</code> {{Deprecated_Inline}}</td>
    <td><code>6</code></td>
   </tr>
   <tr>
    <td><code>PROCESSING_INSTRUCTION_NODE</code></td>
    <td><code>7</code></td>
   </tr>
   <tr>
    <td><code>COMMENT_NODE</code></td>
    <td><code>8</code></td>
   </tr>
   <tr>
    <td><code>DOCUMENT_NODE</code></td>
    <td><code>9</code></td>
   </tr>
   <tr>
    <td><code>DOCUMENT_TYPE_NODE</code></td>
    <td><code>10</code></td>
   </tr>
   <tr>
    <td><code>DOCUMENT_FRAGMENT_NODE</code></td>
    <td><code>11</code></td>
   </tr>
   <tr>
    <td><code>NOTATION_NODE</code> {{Deprecated_Inline}}</td>
    <td><code>12</code></td>
   </tr>
  </tbody>
 </table>
 </dd>
 <dt>{{DOMxRef("Node.nodeValue")}}</dt>
 <dd>Returns / Sets the value of the current node.</dd>
 <dt>{{DOMxRef("Node.ownerDocument")}}{{ReadOnlyInline}}</dt>
 <dd>Returns the {{DOMxRef("Document")}} that this node belongs to. If the node is itself a document, returns <code>null</code>.</dd>
 <dt>{{DOMxRef("Node.parentNode")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("Node")}} that is the parent of this node. If there is no such node, like if this node is the top of the tree or if doesn't participate in a tree, this property returns <code>null</code>.</dd>
 <dt>{{DOMxRef("Node.parentElement")}}{{ReadOnlyInline}}</dt>
 <dd>Returns an {{DOMxRef("Element")}} that is the parent of this node. If the node has no parent, or if that parent is not an {{DOMxRef("Element")}}, this property returns <code>null</code>.</dd>
 <dt>{{DOMxRef("Node.previousSibling")}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("Node")}} representing the previous node in the tree, or <code>null</code> if there isn't such node.</dd>
 <dt>{{DOMxRef("Node.textContent")}}</dt>
 <dd>Returns / Sets the textual content of an element and all its descendants.</dd>
</dl>

<h3 id="Obsolete_properties">Obsolete properties</h3>

<dl>
 <dt>{{DOMxRef("Node.localName")}} {{Obsolete_Inline}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("DOMString")}} representing the local part of the qualified name of an element.
 <div class="blockIndicator note">
 <p><strong>Note:</strong> In Firefox 3.5 and earlier, the property upper-cases the local name for HTML elements (but not XHTML elements). In later versions, this does not happen, so the property is in lower case for both HTML and XHTML.</p>
 </div>
 </dd>
 <dt>{{DOMxRef("Node.namespaceURI")}} {{Obsolete_Inline}}{{ReadOnlyInline}}</dt>
 <dd>The namespace URI of this node, or <code>null</code> if it is no namespace.
 <div class="blockIndicator note">
 <p><strong>Note:</strong> In Firefox 3.5 and earlier, HTML elements are in no namespace. In later versions, HTML elements are in the <code><a class="linkification-ext external" href="https://www.w3.org/1999/xhtml/">http://www.w3.org/1999/xhtml/</a></code> namespace in both HTML and XML trees.</p>
 </div>
 </dd>
 <dt>{{DOMxRef("Node.nodePrincipal")}} {{Non-standard_inline}}{{Obsolete_Inline("gecko46")}}{{Fx_MinVersion_Inline("3")}}</dt>
 <dd>A {{Interface("nsIPrincipal")}} representing the node principal.</dd>
 <dt>{{DOMxRef("Node.prefix")}} {{Obsolete_Inline}}{{ReadOnlyInline}}</dt>
 <dd>Is a {{DOMxRef("DOMString")}} representing the namespace prefix of the node, or <code>null</code> if no prefix is specified.</dd>
 <dt>{{DOMxRef("Node.rootNode")}} {{Obsolete_Inline}}{{ReadOnlyInline}}</dt>
 <dd>Returns a {{DOMxRef("Node")}} object representing the topmost node in the tree, or the current node if it's the topmost node in the tree. This has been replaced by {{DOMxRef("Node.getRootNode()")}}.</dd>
</dl>

<h2 id="Methods">Methods</h2>

<p><em>Inherits methods from its parent, {{DOMxRef("EventTarget")}}</em>.<sup>[1]</sup></p>

<dl>
 <dt>{{DOMxRef("Node.appendChild()", "Node.appendChild(<var>childNode</var>)")}}</dt>
 <dd>Adds the specified <code><var>childNode</var></code> argument as the last child to the current node.<br>
 If the argument referenced an existing node on the DOM tree, the node will be detached from its current position and attached at the new position.</dd>
 <dt>{{DOMxRef("Node.cloneNode()")}}</dt>
 <dd>Clone a {{DOMxRef("Node")}}, and optionally, all of its contents. By default, it clones the content of the node.</dd>
 <dt>{{DOMxRef("Node.compareDocumentPosition()")}}</dt>
 <dd>Compares the position of the current node against another node in any other document.</dd>
 <dt>{{DOMxRef("Node.contains()")}}</dt>
 <dd>Returns a {{jsxref("Boolean")}} value indicating whether or not a node is a descendant of the calling node.</dd>
 <dt>{{domxref("Node.getBoxQuads()")}} {{experimental_inline}}</dt>
 <dd>Returns a list of the node's CSS boxes relative to another node.</dd>
 <dt>{{DOMxRef("Node.getRootNode()")}}</dt>
 <dd>Returns the context object's root which optionally includes the shadow root if it is available. </dd>
 <dt>{{DOMxRef("Node.hasChildNodes()")}}</dt>
 <dd>Returns a {{jsxref("Boolean")}} indicating whether or not the element has any child nodes.</dd>
 <dt>{{DOMxRef("Node.insertBefore()")}}</dt>
 <dd>Inserts a {{DOMxRef("Node")}} before the reference node as a child of a specified parent node.</dd>
 <dt>{{DOMxRef("Node.isDefaultNamespace()")}}</dt>
 <dd>Accepts a namespace URI as an argument and returns a {{jsxref("Boolean")}} with a value of <code>true</code> if the namespace is the default namespace on the given node or <code>false</code> if not.</dd>
 <dt>{{DOMxRef("Node.isEqualNode()")}}</dt>
 <dd>Returns a {{jsxref("Boolean")}} which indicates whether or not two nodes are of the same type and all their defining data points match.</dd>
 <dt>{{DOMxRef("Node.isSameNode()")}}</dt>
 <dd>Returns a {{jsxref("Boolean")}} value indicating whether or not the two nodes are the same (that is, they reference the same object).</dd>
 <dt>{{DOMxRef("Node.lookupPrefix()")}}</dt>
 <dd>Returns a {{DOMxRef("DOMString")}} containing the prefix for a given namespace URI, if present, and <code>null</code> if not. When multiple prefixes are possible, the result is implementation-dependent.</dd>
 <dt>{{DOMxRef("Node.lookupNamespaceURI()")}}</dt>
 <dd>Accepts a prefix and returns the namespace URI associated with it on the given node if found (and <code>null</code> if not). Supplying <code>null</code> for the prefix will return the default namespace.</dd>
 <dt>{{DOMxRef("Node.normalize()")}}</dt>
 <dd>Clean up all the text nodes under this element (merge adjacent, remove empty).</dd>
 <dt>{{DOMxRef("Node.removeChild()")}}</dt>
 <dd>Removes a child node from the current element, which must be a child of the current node.</dd>
 <dt>{{DOMxRef("Node.replaceChild()")}}</dt>
 <dd>Replaces one child {{DOMxRef("Node")}} of the current one with the second one given in parameter.</dd>
</dl>

<h3 id="Obsolete_methods">Obsolete methods</h3>

<dl>
 <dt>{{DOMxRef("Node.getFeature()")}} {{Obsolete_Inline}}</dt>
 <dd></dd>
 <dt>{{DOMxRef("Node.getUserData()")}} {{Obsolete_Inline}}</dt>
 <dd>Allows a user to get some {{DOMxRef("DOMUserData")}} from the node.</dd>
 <dt>{{DOMxRef("Node.hasAttributes()")}} {{Obsolete_Inline}}</dt>
 <dd>Returns a {{jsxref("Boolean")}} indicating if the element has any attributes, or not.</dd>
 <dt>{{DOMxRef("Node.isSupported()")}} {{Obsolete_Inline}}</dt>
 <dd>Returns a {{jsxref("Boolean")}} flag containing the result of a test whether the DOM implementation implements a specific feature and this feature is supported by the specific node.</dd>
 <dt>{{DOMxRef("Node.setUserData()")}} {{Obsolete_Inline}}</dt>
 <dd>Allows a user to attach, or remove, {{DOMxRef("DOMUserData")}} to the node.</dd>
</dl>

<h2 id="Examples">Examples</h2>

<h3 id="Remove_all_children_nested_within_a_node">Remove all children nested within a node</h3>

<pre class="brush: js">function removeAllChildren(element) {
  while (element.firstChild) {
    element.removeChild(element.firstChild)
  }
}</pre>

<h4 id="Sample_usage">Sample usage</h4>

<pre class="brush: js;">/* ... an alternative to document.body.innerHTML = "" ... */
removeAllChildren(document.body)</pre>

<h3 id="Recurse_through_child_nodes">Recurse through child nodes</h3>

<p>The following function recursively calls a callback function for each node contained by a root node (including the root itself):</p>

<pre class="brush: js;">function eachNode(rootNode, callback) {
	if (!callback) {
		const nodes = []
		eachNode(rootNode, function(node) {
			nodes.push(node)
		})
		return nodes
	}

	if (false === callback(rootNode)) {
		return false
    }

	if (rootNode.hasChildNodes()) {
		const nodes = rootNode.childNodes
		for (let i = 0, l = nodes.length; i &lt; l; ++i) {
			if (false === eachNode(nodes[i], callback)) {
				return
            }
        }
	}
}
</pre>

<h4 id="Syntax">Syntax</h4>

<pre class="syntaxbox">eachNode(<var>rootNode</var>, <var>callback</var>)</pre>

<h4 id="Description">Description</h4>

<p>Recursively calls a function for each descendant node of <code><var>rootNode</var></code> (including the root itself).</p>

<p>If <code><var>callback</var></code> is omitted, the function returns an {{jsxref("Array")}} instead, which contains <code><var>rootNode</var></code> and all nodes contained within.</p>

<p>If <code><var>callback</var></code> is provided, and it returns {{jsxref("Boolean")}} <code>false</code> when called, the current recursion level is aborted, and the function resumes execution at the last parent's level. This can be used to abort loops once a node has been found (such as searching for a text node which contains a certain string).</p>

<h4 id="Parameters">Parameters</h4>

<dl>
 <dt><code><var>rootNode</var></code></dt>
 <dd>The <code>Node</code> object whose descendants will be recursed through.</dd>
 <dt><code><var>callback</var></code> {{optional_inline}}</dt>
 <dd>An optional callback <a href="/en-US/docs/JavaScript/Reference/Global_Objects/Function">function</a> that receives a <code>Node</code> as its only argument. If omitted, <code>eachNode</code> returns an {{jsxref("Array")}} of every node contained within <code><var>rootNode</var></code> (including the root itself).</dd>
</dl>

<h4 id="Sample_usage_2">Sample usage</h4>

<p>The following example prints the <a href="/en-US/docs/Web/API/Node/textContent"><code>textContent</code></a> properties of each <code>&lt;span&gt;</code> tag in a <code>&lt;div&gt;</code> element named <code>"box"</code>:</p>

<pre class="brush: html;">&lt;div id="box"&gt;
  &lt;span&gt;Foo&lt;/span&gt;
  &lt;span&gt;Bar&lt;/span&gt;
  &lt;span&gt;Baz&lt;/span&gt;
&lt;/div&gt;</pre>

<pre class="brush: js;">const box = document.getElementById("box")
eachNode(box, function(node) {
  if (null != node.textContent) {
    console.log(node.textContent)
  }
})</pre>

<p>The above will result in the following strings printing to the user's console:</p>

<pre class="brush: js;">"\n\t", "Foo", "\n\t", "Bar", "\n\t", "Baz"</pre>

<div class="blockIndicator note">
<p><strong>Note:</strong> Whitespace forms part of a {{DOMxRef("Text")}} node, meaning indentation and newlines form separate <code>Text</code> between the <code>Element</code> nodes.</p>
</div>

<h4 id="Realistic_usage">Realistic usage</h4>

<p>The following demonstrates a real-world use of the <code>eachNode()</code> function: searching for text on a web-page.</p>

<p>We use a wrapper function named <code>grep</code> to do the searching:</p>

<pre class="brush: js;">function grep(parentNode, pattern) {
	const matches = []
	let endScan = false

	eachNode(parentNode, function(node){
		if (endScan) {
			return false
        }

		// Ignore anything which isn't a text node
		if (node.nodeType !== Node.TEXT_NODE) {
			return
        }

		if (typeof pattern === "string") {
			if (-1 !== node.textContent.indexOf(pattern)) {
				matches.push(node)
            }
		}
		else if (pattern.test(node.textContent)) {
			if (!pattern.global) {
				endScan = true
				matches = node
			}
			else {
                matches.push(node)
            }
		}
	})

	return matches
}</pre>

<p>For example, to find {{DOMxRef("Text")}} nodes that contain typos:</p>

<pre class="brush: js;">const typos = ["teh", "adn", "btu", "adress", "youre", "msitakes"]
const pattern = new RegExp("\\b(" + typos.join("|") + ")\\b", "gi")
const mistakes = grep(document.body, pattern)
console.log(mistakes)
</pre>

<h2 id="Specifications">Specifications</h2>

<table class="standard-table">
 <thead>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
 </thead>
 <tbody>
  <tr>
   <td>{{SpecName("DOM WHATWG", "#interface-node", "Node")}}</td>
   <td>{{Spec2("DOM WHATWG")}}</td>
   <td>Added the following methods: <code>getRootNode()</code></td>
  </tr>
  <tr>
   <td>{{SpecName("DOM4", "#interface-node", "Node")}}</td>
   <td>{{Spec2("DOM4")}}</td>
   <td>Removed the following properties: <code>attributes</code>, <code>namespaceURI</code>, <code>prefix</code>, and <code>localName</code>.<br>
    Removed the following methods: <code>isSupported()</code>, <code>hasAttributes()</code>, <code>getFeature()</code>, <code>setUserData()</code>, and <code>getUserData()</code>.</td>
  </tr>
  <tr>
   <td>{{SpecName("DOM3 Core", "core.html#ID-1950641247", "Node")}}</td>
   <td>{{Spec2("DOM3 Core")}}</td>
   <td>The methods <code>insertBefore()</code>, <code>replaceChild()</code>, <code>removeChild()</code>, and <code>appendChild()</code> returns one more kind of error (<code>NOT_SUPPORTED_ERR</code>) if called on a {{DOMxRef("Document")}}.<br>
    The <code>normalize()</code> method has been modified so that {{DOMxRef("Text")}} node can also be normalized if the proper {{DOMxRef("DOMConfiguration")}} flag is set.<br>
    Added the following methods: <code>compareDocumentPosition()</code>, <code>isSameNode()</code>, <code>lookupPrefix()</code>, <code>isDefaultNamespace()</code>, <code>lookupNamespaceURI()</code>, <code>isEqualNode()</code>, <code>getFeature()</code>, <code>setUserData()</code>, and <code>getUserData().</code><br>
    Added the following properties: <code>baseURI</code> and <code>textContent</code>.</td>
  </tr>
  <tr>
   <td>{{SpecName("DOM2 Core", "core.html#ID-1950641247", "Node")}}</td>
   <td>{{Spec2("DOM2 Core")}}</td>
   <td>The <code>ownerDocument</code> property was slightly modified so that {{DOMxRef("DocumentFragment")}} also returns <code>null</code>.<br>
    Added the following properties: <code>namespaceURI</code>, <code>prefix</code>, and <code>localName</code>.<br>
    Added the following methods: <code>normalize()</code>, <code>isSupported()</code> and <code>hasAttributes()</code>.</td>
  </tr>
  <tr>
   <td>{{SpecName("DOM1", "level-one-core.html#ID-1950641247", "Node")}}</td>
   <td>{{Spec2("DOM1")}}</td>
   <td>Initial definition.</td>
  </tr>
 </tbody>
</table>

<h2 id="Browser_compatibility">Browser compatibility</h2>



<p>{{Compat("api.Node")}}</p>