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[jsp]代码库

<%@ page language="java" contentType="text/html; charset=gbk"  
    pageEncoding="gbk"%>  
      
<%@ page import="java.sql.*" %>  
  
<%!  
String str="";  
private void tree(Connection conn,int id,int level){  
    Statement stmt = null;  
    ResultSet rs = null;  
    String preStr="";  
      
    //前导缩进level表示缩进的层次  
    for(int i=0;i<level;i++){  
        preStr+="----";  
    }  
      
    try{  
        stmt = conn.createStatement();  
        String url = "select * from articles where pid="+id;  
        rs = stmt.executeQuery(url);  
          
        while(rs.next()){             
            str += "<tr><td>"+rs.getInt("id")+"</td><td>"+ preStr +  
                "<a href='detail.jsp?id="+rs.getInt("id")+"'>"+  
                rs.getString("title") +"</a>"+ "</td></tr>";  
            if(rs.getInt("isleaf")!=0){//不是叶子节点  
                tree(conn,rs.getInt("id"),level+1);//如果不是叶子节点,则缩进+1  
            }  
        }  
    }catch(SQLException sql){  
        sql.printStackTrace();  
    }finally{  
        try{  
            if(rs!=null){  
                rs.close();  
                rs=null;  
            }  
            if(stmt!=null){  
                stmt.close();  
                stmt=null;  
            }  
        }catch(SQLException e){  
            e.printStackTrace();  
        }  
    }  
}  
 %>  
  
<%  
Class.forName("com.mysql.jdbc.Driver");  
String url = "jdbc:mysql://localhost/bbs?user=root&password=root";  
Connection conn = DriverManager.getConnection(url);  
  
Statement stmt = conn.createStatement();  
ResultSet rs = stmt.executeQuery("select * from articles where pid=0");  
  
while(rs.next()){  
    str += "<tr><td>"+rs.getInt("id")+"</td><td>"+rs.getString("cont")+"</td></tr>";  
    if(rs.getInt("isleaf")!=0){  
        tree(conn,rs.getInt("id"),1);  
    }  
}  
rs.close();  
stmt.close();  
conn.close();  
%>