2017-3-31 js on element Properties. Operation of the content. Timer. The level of the element, the parent, and the subset relationship.

JS action on element content:

1. Operation Style (style)

2. Operation Properties (Attribute)

3. Operation Contents (Innerhtml/text)

One. Manipulating element properties

Common Properties: Class. Id. Style Disabled

Custom properties: You can customize an arbitrary property name, and you can place the value arbitrarily, without any effect on the element itself.

This: Represents the nearest method.

Set a property: A.setattribute ("Property name", "property value"); "When the property name does not exist, create this property and assign a value. When the property name exists, the value of the property is overwritten. 】

Gets the value of the property: A.getattribute ("property name"); "can get the value of a custom property"

Remove an attribute: A.removeattribute ("attribute name");

Two. Manipulating element content

1. Gets the contents of the form class element "[Form form] basic 12 form class elements." Details: http://www.cnblogs.com/kissdodog/archive/2013/01/10/2854917.html "

Method of Value: a.value= "";

2. Get the content of non-form class elements "div/span, etc."

Method of Value:

(1) a.innertext= "";

When adding content: "When there is a tag inside the element, the tag is executed, but the tag is not displayed"

A.innerhtml= "AAA<BR/>AAA"

Flags are executed <br/> a newline is generated, but not a realistic tag.

When getting content: "When a tag exists inside the element, the markup and the string contents are displayed together"

<div id= "a";><span>aaaa</span><div>

Gets the element with ID:<span>aaa<span> as the content

(2) a.innerhtml= "";

Add content: "Gets the text content inside the element only, the markup is displayed, but does not execute"

A.innerhtml= "AAA<BR/>AAA"

Added after: aaa<br/>aaa

Get content: "Show only string content, no markup"

<div id= "a";><span>aaaa</span><div>

Gets the content of the element with ID A: AAA

3. Common applications

(1) Create a <div class= "H1" ></div>

"1" a.innerhtml ("<div class=" H1 "></div>");

[This method produces an overlay effect when used, and ' + = ' is used when creating multiple]

"2" var a=document.createelement ("div");

A.setattribute ("Class", "H1");

(2) Automatic line-wrapping:;

Three. Timer

(1) Timers that can only be executed once

Window.settimeout (function () {}, execution countdown); "1000 milliseconds = 1 seconds"

(2) A timer that will not be terminated

Window.setinterval (function () {}, interval milliseconds); "1000 milliseconds = 1 seconds"

Termination method:

var a=window.setinterval (function () {}, time interval milliseconds);

Window.clearinterval (a);

Four. Level, child, parent relationship

"Level, child space and newline count a location"

Parent of element A: A.parentnode

The previous element in the peer of element A: A.previoussibling and the previous a.previoussibling.previoussibling

The next element in the middle of element a: a.nextsibling another a.nextsibling.nextsibling

Child of Element A:

Nth sub-level a.childnodes[n]

First sub-a.firstchild

Last sub-a.lastchild

2017-3-31 js on element Properties. Operation of the content. Timer. The level of the element, the parent, and the subset relationship.