網路程式設計 2009/03/05 上課範例

/* SquareApplet.java */ import java.awt.*; import java.applet.*; //import java.awt.Graphics; import javax.swing.*; public class SquareApplet extends JApplet{ double n, s; public void init(){ String Str=JOptionPane.showInputDialog("輸入一個浮點數："); n = Double.parseDouble(Str); s = n*n; } public void paint(Graphics g){ g.drawRect(40,30, 250,55); g.drawString(n + " 的平方為: " + s, 50,50); } } Structure.html < HTML > < BODY BGCOLOR = PINK > < APPLET CODE = "SquareApplet.class" WIDTH = 300 HEIGHT = 100 > < /APPLET > < /BODY > < /HTML > /* Test.java */ import java.awt.*; import java.applet.*; import javax.swing.JOptionPane; public class Test extends Applet{ int nn; String s=null; public void start (){ s = JOptionPane.showInputDialog("輸入一個整數:"); int n = Integer.parseInt(s); nn = n*n; JOptionPane.showMessageDialog(null, s + "的平方為:" + nn, "標題: 平方",JOptionPane.PLAIN_MESSAGE ); } public void paint(Graphics g){ g.drawString( s + "的平方為:" + nn, 50, 60 ); } } Test.html < HTML > < BODY BGCOLOR = PINK > < APPLET CODE = "Test.class" WIDTH = 300 HEIGHT = 100 > < /APPLET > < /BODY > < /HTML > /* Structure.java */ import javax.swing.*; import java.awt.*; import java.applet.*; public class Structure extends JApplet { JLabel lb1; //1. 啟動這個applet時，首先執行的方法 public void init(){ Container c=getContentPane(); c.setLayout(null); lb1=new JLabel("Java Applet init()"); lb1.setFont(new Font("Arial",Font.BOLD,24)); lb1.setForeground(Color.red); lb1.setSize(250,24); lb1.setLocation(50,50); c.add(lb1); System.out.println("init()"); } //2. 執行init()方法後，接著執行的方法， //只要applet畫面出現一次，就會執行start()方法 public void start(){ lb1.setText("Java Applet start()"); System.out.println("start()"); } //3. 切換到別的網頁時，執行stop()方法 public void stop(){ lb1.setText("Java Applet stop()"); System.out.println("stop()"); } //4. 關閉瀏覽器時，執行stop()方法後，接著執行destroy()方法 public void destroy(){ lb1.setText("Java Applet destroy()"); System.out.println("destroy()"); } } Structure.html < HTML > < BODY BGCOLOR = PINK > < APPLET CODE = "Structure.class" WIDTH = 300 HEIGHT = 100 > < /APPLET > < /BODY > < /HTML >