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Solution to the problem that jquery triggers the change event of select to fail

黄舟

Jun 27, 2017 am 09:48 AM

changejqueryselecteventtrigger

jquery cannot trigger the change event of the drop-down box when the page is loaded for the second time. Start tomcat and enter localhost:8080/aa/list.jsp in the address bar. It can trigger the change event of the drop-down box, but from servlet It doesn’t work after I came here. What’s going on?

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>信息界面</title>
<script type="text/javascript" src="js/jquery-1.4.4.min.js"></script>
<script type="text/javascript">
	$(document).ready(function(){
		
		$("#sel_emp").live(&#39;change&#39;,function(){
			var value = $(&#39;#sel_emp&#39;).val();
			alert(value);
			window.location = "/aa/servlet/Test1Servlet";
		});
		
	});

</script>
</head>
<body>
<select id="sel_emp">
	<option value="1">编号</option>
	<option value="2">姓名</option>
</select>
	<table border="1">
		<tr>
			<th>编号</th>
			<th>姓名</th>
		</tr>
		<c:forEach items="${list }" var="element">
		<tr>
			<td>${element.uid }</td>
			<td>${element.username }</td>
		</tr>
		</c:forEach>
	</table>
</body>
</html>

---------------------servlet

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
		
		Employee employee_01 = new Employee();
		employee_01.setUid("1");
		employee_01.setUsername("张三");
		
		Employee employee_02 = new Employee();
		employee_02.setUid("2");
		employee_02.setUsername("李四");
		
		List<Employee> list = new ArrayList<Employee>();
		list.add(employee_01);
		list.add(employee_02);
		
		request.setAttribute("list", list);
		
		request.getRequestDispatcher("/list.jsp").forward(request, response);

Question supplement:

You mean, after jumping to the page from the servlet, clicking the drop-down menu and selecting a value will not trigger the following:

Quote

# function(){  
#           
#         $("#sel_emp").live(&#39;change&#39;,function(){  
#             var value = $(&#39;#sel_emp&#39;).val();  
#             alert(value);  
#             window.location = "/aa/servlet/Test1Servlet";  
#         }

Is it?

Yes

## Question supplement:

Do you mean , after jumping to the page from the servlet, clicking the drop-down menu and selecting a value, the following will not be triggered:

citation

# function(){  
#           
#         $("#sel_emp").live(&#39;change&#39;,function(){  
#             var value = $(&#39;#sel_emp&#39;).val();  
#             alert(value);  
#             window.location = "/aa/servlet/Test1Servlet";  
#         }

, right?

Yes

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