< meta…/> is used to define page meta information. To define meta information is to specify some name-value pairs. In addition to specifying the id attribute, this element can also specify the following three attributes:
http-equiv: specifies the meta-information name. The name specified by this attribute has special meaning. It can be The browser sends back some useful information to help the browser correctly process the web page content.
name: Specify the name of the meta-information. The name can be specified arbitrarily.
content: Specifies the value of meta information.
Specifying effective keywords for web pages will help search engines include this site.
The common values supported by the http-equiv attribute are mainly as follows:
1.Expires: Specify the expiration time of the web page. Once the web page expires, it must be downloaded from the server again.
<meta http-equiv="Expires" content="Sat Sep 27 16:12:36 CST 2008"/>
2.Pragma: Specifies that the browser is prohibited from accessing the page content from the local disk cache. Once the browser leaves the webpage, it cannot access the page offline. For example:
<meta http-equiv="Pragma" content="no-cache"/>
3.Refresh: Specify how long it takes for the browser to automatically refresh the specified page. For example
<!--设置2秒后自动刷新本页面--><meta http-equiv="Refresh" content="2"/><!--设置2秒后自动刷新http://www.baidu.com--><meta http-equiv="Refresh" content="2;URL=http://www.baidu.com"/>
4.Set-Cookie: Set Cookie. If the web page expires, the cookies on the client will also be deleted.
meta http-equiv="Set-Cookie" content="name=value expires= Sat Sep 27 16:12:36 CST 2008, path=/" />
5.content-Type: Set the content type of the page and the character set used
<meta http-equiv="content-Type" content="text/html; charset=GBK"/>
The above is the detailed content of Introduction to HTML5 header meta. For more information, please follow other related articles on the PHP Chinese website!