登录窗体代码Java java登录窗口代码

登陆界面的java代码怎么写?import java.awt.*; \x0d\x0aimport javax.swing.*; \x0d\x0aimport java.awt.event.*; \x0d\x0aimport java.sql.*; \x0d\x0a\x0d\x0aclass LoginFrm extends JFrame implements ActionListener \x0d\x0a{ \x0d\x0aJLabel lbl1=new JLabel("用户名"); \x0d\x0aJLabel lbl2=new JLabel("密码"); \x0d\x0aJTextField txt=new JTextField(15); \x0d\x0aJPasswordField pf=new JPasswordField(); \x0d\x0aJButton btn1=new JButton("确定"); \x0d\x0aJButton btn2=new JButton("取消"); \x0d\x0a\x0d\x0apublic LoginFrm() \x0d\x0a{ \x0d\x0athis.setTitle("登陆"); \x0d\x0aJPanel jp=(JPanel)this.getContentPane(); \x0d\x0ajp.setLayout(new GridLayout(3,2,10,10)); \x0d\x0ajp.add(lbl1);jp.add(txt); \x0d\x0ajp.add(lbl2);jp.add(pf); \x0d\x0ajp.add(btn1);jp.add(btn2); \x0d\x0abtn1.addActionListener(this); \x0d\x0abtn2.addActionListener(this); \x0d\x0a} \x0d\x0a\x0d\x0apublic void actionPerformed(ActionEvent ae) \x0d\x0a{ \x0d\x0aif(ae.getSource()==btn1) \x0d\x0a{ \x0d\x0atry \x0d\x0a{ \x0d\x0aClass.forName("sun.jdbc.odbc.JdbcOdbcDriver")登录窗体代码Java; \x0d\x0aConnection con=DriverManager.getConnection("jdbc:odbc:MyDB","",""); \x0d\x0aStatement cmd=con.createStatement(); \x0d\x0aResultSet rs=cmd.executeQuery("select * from loginAndpassword where login='"+txt.getText()+"' and password='"+pf.getText()+"'"); \x0d\x0aif(rs.next()) \x0d\x0a{ \x0d\x0aJOptionPane.showMessageDialog(null,"登陆成功登录窗体代码Java!"); \x0d\x0a} \x0d\x0aelse \x0d\x0aJOptionPane.showMessageDialog(null,"用户名或密码错误登录窗体代码Java!"); \x0d\x0a} catch(Exception ex){} \x0d\x0a\x0d\x0aif(ae.getSource()==btn2) \x0d\x0a{ \x0d\x0atxt.setText(""); \x0d\x0apf.setText(""); \x0d\x0a} \x0d\x0a} \x0d\x0a} \x0d\x0a\x0d\x0apublic static void main(String arg[]) \x0d\x0a{ \x0d\x0aJFrame.setDefaultLookAndFeelDecorated(true); \x0d\x0aLoginFrm frm=new LoginFrm(); \x0d\x0afrm.setSize(400,200); \x0d\x0afrm.setVisible(true); \x0d\x0a} \x0d\x0a}
用java程序编写一个简单的登录界面怎么写?程序如下:
mport java.awt.HeadlessException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
@SuppressWarnings("serial")
public class MainFrame extends JFrame {
JLabel lbl1 = new JLabel("用户名:");
JLabel lbl2 = new JLabel("密码:");
JTextField txt = new JTextField("admin",20);
JPasswordField pwd = new JPasswordField(20);
JButton btn = new JButton("登录");
JPanel pnl = new JPanel();
private int error = 0;
public MainFrame(String title) throws HeadlessException {
super(title);
init();
}
private void init() {
this.setResizable(false);
pwd.setEchoChar('*');
pnl.add(lbl1);
pnl.add(txt);
btn.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
if ("admin".equal花憨羔窖薏忌割媳公颅s(new String(pwd.getPassword()))){
pnl.removeAll();
JLabel lbl3 = new JLabel();
ImageIcon icon = new ImageIcon(this.getClass().getResource("pic.jpg"));
lbl3.setIcon(icon);
pnl.add(lbl3);
}
else{
if(error3){
JOptionPane.showMessageDialog(null,"密码输入错误 , 请再试一次");
error++;
}
else{
JOptionPane.showMessageDialog(null,"对不起,您不是合法用户");
txt.setEnabled(false);
pwd.setEnabled(false);
btn.setEnabled(false);
}
}
}
});
}
public static void main(String[] args) {
MainFrame frm = new MainFrame("测试");
frm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frm.setBounds(100, 100, 300, 120);
frm.setVisible(true);
}
}
编程的注意事项:
1、Java是一门面向对象编程语言 , 不仅吸收登录窗体代码Java了C++语言的各种优点,还摒弃登录窗体代码Java了C++里难以理解的多继承、指针等概念,因此Java语言具有功能强大和简单易用两个特征 。Java语言作为静态面向对象编程语言的代表,极好地实现了面向对象理论,允许程序员以优雅的思维方式进行复杂的编程 。

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