怎么用JS实现输入编码可以从数据库中找到对应的名称并填写在对应的文本框中。要求默认输入的文本框为编码

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怎么用JS实现输入编码可以从数据库中找到对应的名称并填写在对应的文本框中。要求默认输入的文本框为编码,第1张

第一步是:你要创建一个web前端

为了方便我的书写,我的代码密码为password,请你原谅

<%@ page language="java" contentType="text/htmlcharset=UTF-8"

pageEncoding="UTF-8"%>

<!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/htmlcharset=UTF-8">

<title>登陆</title>

<script type="text/javascript">

function checkInput() {

var oUsername = document.loginForm.username.value

if(oUsername == "") {

alert("没有输入姓名!")

oUsername.select()

return false

}

var oUsercode = document.loginForm.password.value

if(oPassword == "") {

alert("请输入密码!")

oPassword.select()

return false

}

return true

}

</script>

</head>

<body>

<form name="loginForm" action="doLogin.jsp" method="post" onsubmit="return checkInput()">

用户名:<input name="username" type="text" /><br/><br/>

密码:<input name="password" type="password" /><br/><br/>

<input type="submit" value="登陆" />

</form>

</body>

</html>

第二步是dologin.jsp进行服务端验证,然后调用dao层。dao层是调用数据库里的内容的

<%@page import="com.dao.UserDao"%>

<%@ page language="java" contentType="text/htmlcharset=UTF-8"

pageEncoding="UTF-8"%>

<%

//处理post请求参数的乱码

request.setCharacterEncoding("utf-8")

//接收用户输入的用户和密码

String strUsername = request.getParameter("username")

String strPassword = request.getParameter("password")

//服务端验证

if(strUsername == null || "".equals(strUsername.trim())) {

out.println("<script>alert('用户名不能为空')window.location.href='login.jsp'</script>")

return

}

if(strPassword == null || "".equals(strPassword.trim())) {

out.println("<script>alert('密码不能为空!')window.location.href='login.jsp'</script>")

return

}

//用户通过服务端的jsp验证后,然后调用服务端的数据库来进行比对。判断用户的输入的信息是否正确

//调用dao层方法

UserDao userDao = new UserDao()

boolean result = userDao.checkLogin(strUsername, strPassword)

if (result) {

response.sendRedirect("index.jsp")

} else {

out.println("<script>alert('登陆失败')window.location.href='login.jsp'</script>")

}

%>

第三步是dao层了,dao层有连接数据和关闭数据库

package com.dao

import java.sql.Connection

import java.sql.DriverManager

import java.sql.PreparedStatement

import java.sql.ResultSet

import java.sql.SQLException

import java.util.ResourceBundle

//连接数据库和关闭数据库的资源的功能

public class BaseDao {

private ResourceBundle rb = ResourceBundle.getBundle("db")

/**

* 获得数据库的连接

* @return

*/

public Connection getConn() {

Connection conn = null

try {

Class.forName(rb.getString("driver"))

conn = DriverManager.getConnection(rb.getString("url"), rb.getString("dbname"), rb.getString("dbpass"))

} catch (ClassNotFoundException e) {

e.printStackTrace()

}catch (SQLException e) {

e.printStackTrace()

}

return conn

}

/**

* 关闭资源

*/

public void closeAll(ResultSet rs, PreparedStatement pstmt, Connection conn) {

if(rs != null) {

try {

rs.close()

} catch (SQLException e) {

e.printStackTrace()

}

}

if(pstmt != null) {

try {

pstmt.close()

} catch (SQLException e) {

e.printStackTrace()

}

}

try {

if(conn != null &&!conn.isClosed()) {

}

} catch (SQLException e) {

e.printStackTrace()

}

}

}

第四步是UserDao的java文件

package com.dao

import java.sql.Connection

import java.sql.PreparedStatement

import java.sql.ResultSet

import java.util.ArrayList

import java.util.List

import com.entity.User

public class UserDao extends BaseDao{

/**

* 根据用户名和密码验证成功登陆或失败

* param username

* param password

* return 登陆成功 true 失败false

*/

public boolean checkLogin(String username, String password) {

boolean result = false

Connection conn = getConn()

PreparedStatement pstmt = null

ResultSet rs = null

try {

conn = getConn()

String sql = "select * from emp where username=? and password=?"

pstmt = conn.prepareStatement(sql)

pstmt.setString(1, username)

pstmt.setString(2, password)

rs = pstmt.executeQuery()

if(rs.next()) {

result = true

}

} catch (Exception e) {

e.printStackTrace()

} finally {

closeAll(rs, pstmt, conn)

/*rs.close()

pstmt.close()

conn.close()*/

}

return result

}

}

第五步是编辑db.properties文件

driver=oracle.jdbc.driver.OracleDriver

url=jdbc:oracle:thin:@localhost:1521:orcl

dbname=scott

dbpass=tiger

测试的电脑已经装好Oracle客户端,而且用SQLplus可以连接上。

/*

* This sample shows how to list all the names from the EMP table

*

* It uses the JDBC THIN driver. See the same program in the

* oci8 samples directory to see how to use the other drivers.

*/

// You need to import the java.sql package to use JDBC

import java.sql.*

class Test

{

public static void main (String args [])

throws SQLException

{

// Load the Oracle JDBC driver

DriverManager.registerDriver(new oracle.jdbc.OracleDriver())

/* try{

Class.forName("oracle.jdbc.driver.OracleDriver")

}catch(Exception e){

System.out.println("No Driver!")

}

*/

// Connect to the database

// You must put a database name after the @ sign in the connection URL.

// You can use either the fully specified SQL*net syntax or a short cut

// syntax as <host>:<port>:<sid>. The example uses the short cut syntax.

String url = "jdbc:oracle:thin:@172.28.31.85:1521:YIKATONG"

String userName = "scott"

String password = "tiger"

if (args.length >0) url = args[0]

if (args.length >1) userName = args[1]

if (args.length >2) password = args[2]

System.out.println(url)

System.out.println(userName)

System.out.println(password)

Connection conn =

DriverManager.getConnection (url, userName, password)

// Create a Statement

Statement stmt = conn.createStatement ()

// Select the ENAME column from the EMP table

ResultSet rset = stmt.executeQuery ("select * from Test")

// Iterate through the result and print the employee names

while (rset.next ())

System.out.println (rset.getString (1))

}

}

补充日期: 2005-03-14 20:20:29

Java与Oracle的两种连接方式

src=>(作者:huihoo)

第一种方式:通过数据库本身的JDBC Driver连接到数据库

Classs.forName("oracle.jdbc.driver.OracleDriver")

Connection conn = DriverManager.getConnection("jdbc:oracle:thin:@192.168.1.33:1521:huihoo","scott","tiger")

第二种方式:通过JDBC-ODBC桥连接到数据库

Class.forName("sun.jdbc.odbc.JdbcOdbcDriver")

Connection conn = DriverManager.getConnection("jdbc:odbc:192.168.1.33","scott","tiger")

192.168.1.33为数据源

完整的用户登录

Properties props = new Properties()

props.put("user", "scott")

props.put("password", "tiger")

Driver myDriver = (Driver) Class.forName("oracle.jdbc.driver.OracleDriver").newInstance()

conn = myDriver.connect("jdbc:oracle:thin:@192.168.1.33:1521:huihoo", props)

conn.close()

System.out.println("成功登录.")

System.out.println("欢迎您 "+props.getProperty("user")+"!")

尝试获取数据,如果报错,特别是报连接断开的错误,则表明已经断开

router.get('/', function (req, res, next) {var oracledb = require('oracledb')

oracledb.getConnection(

{

user: 'username',

password: 'password',

connectString: '192.168.20.10:1521/ORCL'

},function (err, connection) {if (err) {

console.error(err.message) return

}

connection.execute("SELECT * from CMS_FIlE where content_id=:id",

[1072], // bind value for :id

function (err, result) {if (err) {

console.error(err.message) return

}

res.render('index', {title: '查询信息:' + JSON.stringify(result.rows)})

})

})

})