javaWeb(绑定&删除&查看&修改)

一.绑定

<%
				//数据库交互oracleDriver
				//加载驱动
				Class.forName("oracle.jdbc.driver.OracleDriver");
				//建立连接
				Connection conn=DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl", "scott","123");
				//sql
				String sql="select *from tb_t281_news";
				PreparedStatement ps=conn.prepareStatement(sql);
				//返回结果集对象
				ResultSet rs=ps.executeQuery();
				//遍历
				while(rs.next()){
					out.print("
"+rs.getString(3)+"  作者："+rs.getString(4)+"     修改      删除 
");
				}

%>

二.删除

String sql="DELETE TB_XW WHERE NID=?";
PreparedStatement ps=con.prepareStatement(sql);

String id=request.getParameter("id");
	ps.setInt(1, Integer.parseInt(id));
	 int n=ps.executeUpdate();
	if(con!=null&&!con.isClosed()){
		con.close();
	}
	if(ps!=null){
		ps.close();
	}
	if(n>0){
		request.getRequestDispatcher("xwfind.jsp").forward(request, response);
	}else{
		out.print("");
	} 

三.查看

<%
String URL="jdbc:oracle:thin:@localhost:1521:orcl";
String CNAME="oracle.jdbc.driver.OracleDriver";
Class.forName(CNAME);
Connection con=DriverManager.getConnection(URL, "scott", "tiger");
String sql="select * from tb_xw where nid=?";
PreparedStatement ps=con.prepareStatement(sql);
ps.setInt(1, Integer.parseInt(request.getParameter("id")));
ResultSet rs=ps.executeQuery();
String nname="";
String addtime="";
String nzz="";
String nnr="";
while(rs.next()){
	nname=rs.getString(2);
	addtime=rs.getString(7);
	nzz=rs.getString(3);
	nnr=rs.getString(5);
}
给文本框赋值使用<%=nnr %>
%>

四.修改

String sql="UPDATE TB_XW SET NNAME=?,NZZ=?,NZY=?,NNR=?,TNAME=? WHERE NID=?";

	PreparedStatement ps=con.prepareStatement(sql);
	ps.setString(1,request.getParameter("nname"));
	ps.setString(2,request.getParameter("nzz"));
	ps.setString(3,request.getParameter("nzy"));
	ps.setString(4,request.getParameter("nnr"));
	ps.setString(5,request.getParameter("tname"));
	ps.setInt(6, Integer.parseInt(request.getParameter("id")));
	int n=ps.executeUpdate();
	
	if(con!=null&&!con.isClosed()){
		con.close();
	}
	if(ps!=null){
		ps.close();
	}
	
	if(n>0){
		out.print("");
	}else{
		out.print("");
	}