无线传感器网络项目（温室）(4)
Aims:
To build an economical, energy- saving and easy-to-operating greenhouse control system。
Method:
HTML, CSS and JavaScript language
Socket。io
Hardware requirements
Arduino Mega 2560
Intel Galileo Gen 1
Telegesis ETRX357 ZigBee
Software requirements
Arduino IDE
PuTTY
WinSCP
Node。js
Telegesis Terminal
Notepad++
Chapter I: BACKGROUND
1。 Create a Web Page
The three main technologies used to create web pages (HTML, CSS and JavaScript) each do different special jobs。[1]
HTML should be used only for structuring content。
Cascading Style Sheets should be used for applying all visual styles。
JavaScript should be used for (almost) all interactive functionality, and should always be referenced in separate files, never written into HTML。
Figure 1: the relationship between HTML, CCS and JavaScript
1。1HTML
HTML Overview
HTML stands for Hypertext Markup Language, and it is the most widely used language to write Web Pages。 HTML is a format that tells a computer how to display a web page。 The documents themselves are plain text files with special "tags" or codes that a web browser uses to interpret and display information on the computer screen。 [2]
Hypertext refers to the way in which Web pages (HTML documents) are linked together。 Thus, the link available on a webpage is called Hypertext。
HTML stands for Hyper Text Markup Language which means HTML is simply "mark-up" a text document with tags that tell a Web browser how to structure it to display。
An HTML file is a text file containing small markup tags
The markup tags tell the Web browser how to display the page
An HTML file must have an htm or html file extension文献综述
Originally, HTML was developed with the intent of defining the structure of documents like headings, paragraphs, lists, and so forth to facilitate the sharing of scientific information between researchers。
Now, HTML is being widely used to format web pages with the help of different tags available in HTML language。
HTML Basic Tags
HTML is a markup language and makes use of various tags to format the content。 These tags are enclosed within angle braces <Tag Name>。 Except for few tags, most of the tags have their corresponding closing tags。 For example, <html> has its closing tag</html> and <body> tag has its closing tag </body> tag etc。
Above example of HTML document uses the following tags:
Tag Description
<!DOCTYPE。。。> This tag defines the document type and HTML version。
<html> This tag encloses the complete HTML document and mainly comprises of document header which is represented by <head>。。。</head> and document body which is represented by <body>。。。</body> tags。
<head> This tag represents the document's header which can keep other HTML tags like <title>, <link> etc。
<title> The <title> tag is used inside the <head> tag to mention the document title。
<body> This tag represents the document's body which keeps other HTML tags like <h1>, <p>, <p> etc。
<h1> This tag represents the heading。
<p>