JavaScript 查找元素
Posted max-hou
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了JavaScript 查找元素相关的知识，希望对你有一定的参考价值。
javascript 查找元素
查询单个元素document.getElementById
示例
|
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
|
<!DOCTYPE html><html> <head> <title>访问元素</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .mycolor color:#fff; </style> </head> <body> <ul id="ul"> <li id="a">油条</li> <li id="b">包子</li> <li id="c">米饺</li> <li id="d"><a>鱼粉</a></li> </ul> <script> // 返回单一元素节点 var el = document.getElementById(‘a‘); el.className=‘mycolor‘; </script> </body></html> |
按CSS查询一个 document.querySelector
按CSS查询
示例1 查询一个
|
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
|
<!DOCTYPE html><html> <head> <title>访问元素</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .mycolor color:#fff; .steam text-decoration: initial; </style> </head> <body> <ul id="ul"> <li id="a">油条</li> <li id="b" class="steam">包子</li> <li id="c" class="steam">米饺</li> <li id="d"><a>鱼粉</a></li> </ul> <script> // 返回一个元素节点 var el = document.querySelector(‘li.steam‘); el.className=‘mycolor‘; </script> </body></html> |
示例2 查询多个
|
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
|
<!DOCTYPE html><html> <head> <title>访问元素</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .mycolor color:#fff; .steam text-decoration: initial; </style> </head> <body> <ul id="ul"> <li id="a">油条</li> <li id="b" class="steam">包子</li> <li id="c" class="steam">米饺</li> <li id="d"><a>鱼粉</a></li> </ul> <script> // 返回多个元素节点 var els = document.querySelectorAll(‘li.steam‘); els[0].className=‘mycolor‘; </script> </body></html> |
按元素标签查询多个 getElementsByTagName
|
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
|
<!DOCTYPE html><html> <head> <title>访问元素</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .mycolor color:#fff; .steam text-decoration: initial; </style> </head> <body> <ul id="ul"> <li id="a">油条</li> <li id="b" class="steam">包子</li> <li id="c" class="steam">米饺</li> <li id="d"><a>鱼粉</a></li> </ul> <script> // 按元素标签查询 var els = document.getElementsByTagName(‘li‘); els[2].className=‘mycolor‘; </script> </body></html> |
查询父节点parentNode
示例
|
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
|
<!DOCTYPE html><html> <head> <title>访问元素</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .mycolor color:#fff; .steam text-decoration: initial; </style> </head> <body> <ul id="ul"> <li id="a">油条</li> <li id="b" class="steam">包子</li> <li id="c" class="steam">米饺</li> <li id="d" ><a id="yufen">鱼粉</a></li> </ul> <script> // 查找父节点 var el = document.getElementById(‘yufen‘); el.parentNode.className="mycolor"; </script> </body></html> |
查找兄弟元素 previousSibling nextSibling
示例
|
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
|
<!DOCTYPE html><html> <head> <title>访问元素</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .mycolor color:#fff; .steam color: red; </style> </head> <body> <ul id="ul"> <li id="ali">油条</li><li id="bli">包子</li><li id="cli">米饺</li><li id="dli"><a id="yufen">鱼粉</a></li> </ul> <script> // 查找父节点 var tempel = document.getElementById("bli"); tempel.className="steam"; var previousNode = tempel.previousSibling; previousNode.className="mycolor"; var nextNode = tempel.nextSibling; nextNode.className="mycolor"; </script> </body></html> |
兄弟元素查找比较坑，只是能元素在同一行时才能查询。
查询子节点 firstChild lastChild
示例
|
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
|
<!DOCTYPE html><html> <head> <title>访问元素</title> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <style> .mycolor color:#fff; .steam color: red; </style> </head> <body> <ul id="ul" ><li id="ali">油条</li ><li id="bli">包子</li ><li id="cli"><a id="yufen">米饺</a></li ><li id="dli">鱼粉</li ></ul> <script> // 查找子节点 var tempel = document.getElementById("ul"); var firstNode = tempel.firstChild; firstNode.className = "mycolor"; var lastNode = tempel.lastChild; lastNode.className = "mycolor"; </script> </body></html> |
以上是关于JavaScript 查找元素的主要内容，如果未能解决你的问题，请参考以下文章
JavaScript 学习-27.查找HTML DOM节点(元素)