jsp如何自定义标签(带参数传递)

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1. package mytag.tag;
   
2. 
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3. import java.io.IOException;
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4. import java.text.SimpleDateFormat;
   
5. import java.util.Date;
   
6. 
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7. import javax.servlet.jsp.JspException;
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8. import javax.servlet.jsp.JspWriter;
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9. import javax.servlet.jsp.PageContext;
   
10. import javax.servlet.jsp.tagext.SimpleTagSupport;
    
11. 
    
12. public class DateTag extends SimpleTagSupport{
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13.     private String quesId;
    
14. @Override
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15. public void doTag() throws JspException, IOException {
    
16.       String message = "";
    
17.   if(quesId.equals("0")){
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18.    message = "你好";
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19.   }else{
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20.    message = "hello";
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21.   }
    
22.   out.println(message);
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23. }
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24. public String getQuesId() {
    
25.   return quesId;
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26. }
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27. public void setQuesId(String quesId) {
    
28.   this.quesId = quesId;
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29. }
    
30. }

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标签文件：

1. <?xml version="1.0" encoding="UTF-8" ?>
   
2. <taglib xmlns="http://java.sun.com/xml/ns/j2ee"
   
3.         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   
4.         xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
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5.         version="2.0">
   
6.         <tlib-version>1.2</tlib-version>
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7.         <short-name>c1</short-name>
   
8.         <uri>http://www.52itstyle.top/mytag</uri>
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9.   <tag>
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10.                   <name>date</name>
    
11.               <tag-class>tag.myTag</tag-class>
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12.               <body-content>empty</body-content>
    
13.               <attribute>
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14.             <name>quesId</name>
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15.             <required>true</required>
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16.             <rtexprvalue>true</rtexprvalue>
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17.         </attribute>
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18.   </tag>
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19. </taglib>

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把以上文件命名mytag.tld 放到WEB-INF 下面 即可
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页面加入：

1. <%@ page language="java" import="java.util.*" pageEncoding="utf-8" isELIgnored="false"%>
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2. <%@taglib uri="/WEB-INF/mytag.tld" prefix="c1"%>
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3. <c1:date quesId="1"/>

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