1 傳值:web.xml傳遞參數
2
3 在web.xml中的Servlet里配置多個init-param
4 <servlet>
5 ...
6 <init-param>
7 <param-name>name</param-name>
8 <param-value>關羽</param-value>
9 </init-param>
10 <init-param>
11 <param-name>age</param-name>
12 <param-value>20</param-value>
13 </init-param>
14 <init-param>
15 <param-name>sex</param-name>
16 <param-value>男</param-value>
17 </init-param>
18 </servlet>
19
20 在servlet的init()方法中:
21 String name=this.getServletConfig().getInitParameter("name");
22 String age=this.getServletConfig().getInitParameter("age");
23
24
25 ServletConfig sc=this.getServletConfig();
//枚舉 獲取所有配置參數信息 26 Enumeration e=sc.getServletConfig().getInitParameterNames();
27 while(e.hasMoreElements()){
28 syso(sc.getInitParameter(e.nextElement().toString()));
29 }
30
31
32 -----------------------------------
33 在web.xml中的web-app下配置多個context-param
34 <context-param>
35 <param-name></param-name>
36 <param-value></param-value>
37 </context-param>
38
39 <context-param>
40 <param-name></param-name>
41 <param-value></param-value>
42 </context-param>
43
44
45 context:一般指上下文環境
46
47 ServletContext:指的是整個web項目的上下文環境 ,表示的就是整個web.xml
48
49 this.getServletContext().getInitParameter("age");
50 //可以通過局部獲得整體(由子到父)
51 this.getServletConfig().getServletContext().getInitParameter("age");
52
53 ServletConfig,ServletContext 可以直接從this(Servlet)中獲得這兩個對象
54 ServletConfig scf=this.getServletConfig();
55 ServletContext sct=this.getServletContext();
56
57 init(),init(ServletConfig config):在GenericServlet中,init(ServletConfig config) 里面調用init(),所以覆蓋的是init(),而不是init(ServletConfig config)