XHTML is a HTML written in XML format. XHTML refers to Extensible Hypertext markup language XHTML and HTML 4.01 are almost the same. XHTML is a stricter and purer version of HTML XHTML is a HTML defined as a XML application. XHTML is a W3C recommendation released in January 2001. XHTML is supported by all major browsers Many pages on the Internet contain “bad” HTML. If you view it in a browser, the following HTML code works perfectly (even if it does not follow the HTML rules): XML is a well-formed markup language that must be tagged correctly. There are some different browser technologies in today’s technology world. Some of them run on computers, while others may run on mobile phones or other small devices. Small devices often lack the resources and ability to explain “bad” markup languages. So-by combining the strengths of XML and HTML, XHTML was developed. XHTML is a redesigned HTML as XML. XHTML DOCTYPE is mandatory. In HTML, some elements can not be nested within each other, like this: In XHTML, all elements must be reasonably nested within each other, like this: Example of error: Correct example: Example of error: Correct example: Example of error: Correct example: Example of error: Correct example: Example of error: Correct example: Example of error: Correct example: Add a XHTML Add Change all elements to lowercase Turn off all empty elements Modify all attribute names to lowercase Add quotation marks to all attribute values
In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress. 11.29.1. What is XHTML? ¶
11.29.2. Why use XHTML? ¶
<html><head><metacharset="utf-8"><title>This is an non-standard
HTMLtitle><body><h1>non-standard HTML<p>This is a paragraphbody>
11.29.3. The most important difference compared to HTML: ¶
Document structure ¶
XML in namespace attribute is mandatory 、 、 11.29.5. XHTML elements must be reasonably nested ¶
<b><i>Bold and Italic Textb>i>
<b><i>Bold and Italic Texti>b>
11.29.6. The XHTML element must be related to a closed tag ¶
<p>This is a paragraph<p>This is another paragraph
<p>This is a paragraphp><p>This is another paragraphp>
11.29.7. An empty element must contain a close tag ¶
branch:<br>horizontal line:<hr>picture:<imgsrc="happy.gif"alt="Happy face">
branch:<br/>horizontal line:<hr/>picture:<imgsrc="happy.gif"alt="Happy face"/>
11.29.8. XHTML element must be lowercase ¶
<BODY><P>This is a paragraphP>BODY>
<body><p>This is a paragraphp>body>
11.29.9. Attribute name must be lowercase ¶
<tableWIDTH="100%">
<tablewidth="100%">
11.29.10. Attribute values must have quotation marks ¶
<tablewidth=100%>
<tablewidth="100%">
11.29.11. Attribute abbreviations are not allowed ¶
<inputchecked><inputreadonly><inputdisabled><optionselected>
<inputchecked="checked"><inputreadonly="readonly"><inputdisabled="disabled"><optionselected="selected">
11.29.12. How to convert HTML to XHTML ¶
go to your web page xmlns property is added to the html element.
Principles, Technologies, and Methods of Geographic Information Systems
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