| 摘 要: 本文从结构伪类与类选择器的比较、结构伪类与文档树的关系、结构伪类的功能与应用等三个层面,深 入阐述了结构伪类的作用,结构伪类所表示的文档树结构,结构伪类通过位置索引定位子元素的机制。通过将定位子元 素的结构伪类分为带参数和不带参数两类,深入论述了带参数结构伪类的参数模式、典型应用及与不带参数结构伪类的 对应关系。 | 
			
	         
				| 关键词: 选择器  结构伪类  文档树  位置索引 | 
		
			 
                     
			
                | 中图分类号: TP391
			 
		
                  文献标识码: A | 
		
	   
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                | Deep Understanding of CSS3 Structural Pseudo-Classes Selectors | 
           
			
                | HUANG Zhigang | 
           
		   
                | ( College of Software, Hunan Vocational College of Science and Technology, Changsha 410118, China) 
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                | Abstract: The article describes deeply the function of the structural pseudo-classes,the document tree structure represented by structural pseudo-classes and structural pseudo-classes’ mechanism of positioning sub-element by means of position index from the aspects of the comparison of the structural pseudo-classes and class selectors,the relationship of the structural pseudo-classes and the document tree as well as the functions and applications of the structural pseudoclasses.The article discusses in detail the parameter model and typical application with parameter structural pseudo-class,the corresponding relations between structural pseudo-class with and without parameters by dividing the structural pseudo-class of positioning sub-element into two classes with and without parameters. | 
	       
                | Keywords: selectors  structural Pseudo-classes  document tree  position index |