回复 2楼 林月儿

我按着你的方法试了下，可还是这个判断不能执行                    if(password.equals(drmm.getText())){

view.setText("登入成功");

完整代码如下：

import java.awt.*;

import java.awt.event.*;

import *;

import *;

import java.sql.*;

import java.util.*;

import javax.swing.*;

import javax.swing.*;

public class test{

public void Dframe(){

JFrame dr=new JFrame("登入界面");

dr.setLayout(null);

dr.setBounds(700,100,200,200);

Container con1=dr.getContentPane();

dr.setVisible(true);

JLabel lable1=new JLabel("账号");

lable1.setBounds(0,20,100,20);

con1.add(lable1);

final JTextField drzh=new JTextField();

drzh.setBounds(30,20,100,20);

drzh.setBackground(Color.yellow);

con1.add(drzh);

final JLabel lable2=new JLabel("密码");

lable2.setBounds(0,40,100,20);

con1.add(lable2);

final JTextField drmm=new JTextField();

drmm.setBounds(30,40,100,20);

drmm.setBackground(Color.yellow);

con1.add(drmm);

final JButton drbt=new JButton("登入");

drbt.setBounds(40,70,60,20);

drbt.setBackground(Color.blue);

con1.add(drbt);

final JLabel view=new JLabel();                                    //创建错误提示框

view.setBounds(40, 100, 200,21);

con1.add(view);

drbt.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e){

Connection con;

final ResultSet res;

String password=null;

try {

Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");

System.out.println("驱动加载成功");

con=DriverManager.getConnection("jdbc:sqlserver://localhost:1433;DatabaseName=ADM","sa","sa");

System.out.println("数据库连接成功");

String sql="select password from USERINTO "+" where userid=?";

PreparedStatement stmt=con.prepareStatement(sql);

stmt.setString(1,drzh.getText());

res=stmt.executeQuery();

if(res.next()){

password=res.getString("password");

}

con.close();

res.close();

} catch (Exception e1) {

// TODO Auto-generated catch block

e1.printStackTrace();

}

if(password==null){

view.setText("账号不存在");

}else{

//System.out.println("3"+drmm.getText());

if(password.equals(drmm.getText())){

//System.out.println("4"+drmm.getText());

view.setText("登入成功");

}else{

view.setText("密码错误");

}

}

}

});

}

public static void main(String args[]){

test main=new test();

main.Dframe();

}

}