检查用户名是否存在jsp——access<%@ page language="java"contentType="text/html; charset=BIG5" pageEncoding="BIG5"%><%@pageimport="java.sql.*"%><!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=BIG5"><title>checkname</title></head><body><% String user1 = request.getParameter("User"); String pass1 = request.getParameter("Pass"); ResultSet rs1; Statement stmt1; PreparedStatement pstmt1; Connection connAcce1; String strURL1; try{ strURL1 = "jdbc:odbc:access"; Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); connAcce1 = DriverManager.getConnection(strURL1,"",""); stmt1 = connAcce1.createStatement(); rs1 = stmt1.executeQuery("SELECT * FROM info"); while(rs1.next()) { if(user1.equals(rs1.getString(2))) { session.setAttribute("error","用名已存在！重新入"); request.getRequestDispatcher("error.jsp").forward( request, response); }else{ pstmt1=connAcce1.prepareStatement("insert into info(用名,密) values(?,?)"); pstmt1.setString(1,user1); pstmt1.setString(2,pass1); session.setAttribute("success","regist success!"); request.getRequestDispatcher("success.jsp").forward( request, response); } } stmt1.close(); connAcce1.close(); }catch(Exception ex) { ex.printStackTrace(); }%></body></html>