VI命令使用(查找替换)

1.在页面中引入dwr的两个js文件
<!-- 列表级联 -->
<script type ="text/javascript" src='<%=basePath %>dwr/engine.js'></script>
<script type="text/javascript" src='<%=basePath %>dwr/util.js'></script>
2.（表单）form的内容如下：
<form action="person.do" method="post" onsubmit="return validate(this);">
<tr>
<td class="tdEditLabel" > 机构：</td>
总:<select name="Org1" id="Org1" onchange="change1(this.value);">
<option>--请选择--</option>
<c:choose>
<c:when test="${empty list}">

</c:when>
<c:otherwise>
<c:forEach items="${list}" var="l">
<option value="${l.id }">${l.description }</option>
</c:forEach>
</c:otherwise>
</c:choose>
</select>
分: <select name="orgId" id="orgid">
</select>
</td>
</tr>
</form>
3.web.xml配置文件必须配置dwr:
<servlet>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
<init-param>
<param-name>debug</param-name>
<param-value>true</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>
4.编写查询数据库的实现类
package com.dywz.track.manager.impl;
import java.util.List;
import java.util.Map;
//查询所有顶级机构(List)

public List Org1() {
String sql = "select * from t_orgnization where fid = ?";
List list = new ArrayList();
Connection con = null;
PreparedStatement pst = null;
ResultSet rst = null;

try{
con = DBConnectionPool.getConnection();
pst = con.prepareStatement(sql);
pst.setString(1, "0");
rst = pst.executeQuery();
while(rst.next()){
Orgnization org = new Orgnization();
org.setId(rst.getInt("id"));
org.setDescription(rst.getString("description"));
org.setFid(rst.getInt("fid"));
list.add(org);
}

}catch(Exception e){
e.printStackTrace();
}finally{
DBConnectionPool.close(rst);
DBConnectionPool.close(pst);
DBConnectionPool.close(con);
}
return list;
}
//查询所有顶级机构的下属机构(Map)
public Map Org2(final int fid) {
String sql = "select * from t_orgnization where fid = ? ";
Map map = new HashMap();

Connection conn = null;
PreparedStatement pst = null;
ResultSet rst = null;
try{
conn = DBConnectionPool.getConnection();
pst = conn.prepareStatement(sql);
pst.setInt(1, fid);
rst = pst.executeQuery();
while(rst.next()){

Orgnization org = new Orgnization();
org.setId(rst.getInt("id"));
org.setDescription(rst.getString("description"));
map.put(org.getId(), org.getDescription());
}

}catch(Exception e){
e.printStackTrace();
}finally{
DBConnectionPool.close(rst);
DBConnectionPool.close(pst);
DBConnectionPool.close(conn);
}

return map;
}
5.在dwr.xml文件中配置实现类
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN" "http://getahead.org/dwr/dwr20.dtd">
<dwr>
<allow>
<create creator="new" javascript="TT">
<param name="class" value="com.dywz.track.manager.impl.OrgManagerImpl"/>
</create>

</allow>
</dwr>
6.在页面配置javascript:

<script type="text/javascript">
function change1(dd){

DWRUtil.removeAllOptions("orgId");
TT.Org2(dd,callback);
}
function callback(data){

DWRUtil.addOptions("orgId",["--请选择--"]);//让第2个下拉框显示“--请选择--”
DWRUtil.addOptions("orgId",data);
}
</script>