This time I will bring you JS access to the selected DOM node (with code). What are the precautions for JS access to the selected DOM node? The following is a practical case, let's take a look.
The example of this article describes the method of JS to access the DOM objectspecified node. Share it with everyone for your reference, the details are as follows:
1 Introduction
Use the getElementById()
method to access the specified id node, and use the nodeName attribute, nodeType attribute and nodeValue attribute to display the node name, node type and node value.
1, nodeNameAttribute
This attribute is used to obtain the name of a node.
[sName=]obj.nodeName
sName: StringThe variable is used to store the name of the node.
2, nodeTypeAttribute
This attribute is used to obtain the type of a node.
[sType=]obj.nodeType
sType: String variable, used to store the type of node, the value of this type is numeric . The type of this parameter is shown in the table below.
Type | Value | Node name | Description |
Element ) | 1 | tag | Any HTML or XML tag |
Attribute | 2 | Attribute | Attribute in tag |
Text (text) | 3 | #text | Contains the text in the tag |
Comment | 8 | #comment | HTML comment |
Document | 9 | #document | Document Object |
Document Type (documentType) | 10 | DOCTYPE | DTD Specification |
3. nodeValueProperty
This property will return the value of the node.
[txt=]obj.nodeValue
txt: String variable is used to store the value of the node, except for text node types. The node values of the type are all "null".
Second application
Access the specified node. In this example, the name of the specified node and the type of the node are displayed in the prompt box that pops up on the page. and the value of the node.
Three codes
nbsp;html> <title></title> <h3 id="三号标题">三号标题</h3> <b>加粗内容</b> <script> <!-- var by=document.getElementById("b1"); var str; str="节点名称:"+by.nodeName+"\n"; str+="节点类型:"+by.nodeType+"\n"; str+="节点值:"+by.nodeValue+"\n"; alert(str); --> </script>
Fourth run will pop up the following prompt box:
I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!
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The above is the detailed content of JS access selected DOM node (with code). For more information, please follow other related articles on the PHP Chinese website!

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