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Detailed explanation of JavaScript local modification and global modification of css style examples

伊谢尔伦

Jul 21, 2017 pm 02:59 PM

cssjavascript

1. Partially changing the style

is divided into three types: changing the direct style, changing the className and changing the cssText. What needs to be noted is:
Pay attention to capitalization:
Javascript is very sensitive to capitalization. ClassName cannot write "N" as "n", and cssText cannot write "T" as "t", otherwise it cannot be implemented. Effect.
Calling method:
If you change className, declare the class in the style sheet in advance, but do not follow style when calling, like document.getElementById('obj').style.className=”…” Incorrect! It can only be written as: document.getElementById('obj').className="..."
Change cssText
But if you use cssText, you must add style. The correct way to write it is: document.getElementById('obj') .style.cssText=”…”

I don’t need to talk about changing the direct style. Just remember to write the specific style, such as

document.getElementById(&#39;obj&#39;).style.backgroundColor=”#003366″

2. Global Changing the style
Normally, we can achieve real-time switching of web page styles by changing the href value of the external link style, that is, "changing the template style". At this time, we first need to give an id to the target that needs to be changed, such as

<link rel = "stylesheet" type="text/css" id="css" href="firefox.css" />

It is very simple to call, such as

<span on click="javascript:document.getElementById(&#39;css&#39;).href = &#39;ie.css&#39;">点我改变样式</span>

For newcomers, they often don’t know that the specific CSS style is in javascript How to write it, and sometimes the requirements are different in different browsers. For example, float is written as styleFloat in IE and cssFloat in FIREFOX, which requires everyone's accumulation. Searching "ccvita javascript" in Google may help your doubts.

Basic knowledge
There are usually three ways to call style sheets in web pages.
First type: Linking to an external style sheet file (Linking to a Style Sheet)
You can create an external style sheet file (.css) first, and then use the HTML link object. An example is as follows:

<head> 
<title>文档标题</title> 
<link rel=stylesheet href="http://www.ccvita.com/demo.css" type="text/css"> 
</link></head>

In XML, you should add it in the declaration area as shown in the following example:

< ? xml-stylesheet type="text/css" href="http://www.dhtmlet.com/dhtmlet.css" ?>

Second: Define internal style block objects ( Embedding a Style Block)
You can insert a block object between the and tags of your HTML document. For definition methods, please refer to style sheet syntax. An example is as follows:

<html> 
<head> 
<title>文档标题</title> 
<style type="text/css"> 
<!-- 
body {font: 10pt "Arial"} 
h1 {font: 15pt/17pt "Arial"; font-weight: bold; color: maroon} 
h2 {font: 13pt/15pt "Arial"; font-weight: bold; color: blue} 
p {font: 10pt/12pt "Arial"; color: black} 
--> 
</style> 
</head> 
<body>  
</body></html>

Please note that setting the type attribute of the style object to "text/css" here allows browsers that do not support this type to ignore the style sheet.

Third type: Inline Definition (Inline Styles)

Inline definition is to use the style attribute of the object within the mark of the object to define the style sheet attributes that apply to it. An example is as follows:

<p style="margin-left: 0.5in; margin-right:0.5in">这一行被增加了左右的外补丁</p><p> </p>

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