科学计算器程序Java代码

1、功能举例：源程序如下：import java.awt.BorderLayout;import java.awt.Color;import java.awt.Dimension;import java.awt.Font;import java.awt.GridLayout;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.text.DecimalFormat;import javax.swing.BorderFactory;import javax.swing.ButtonGrou

2、p;import javax.swing.JButton;import javax.swing.JCheckBoxMenuItem;import javax.swing.JFrame;import javax.swing.JMenu;import javax.swing.JMenuBar;import javax.swing.JMenuItem;import javax.swing.JPanel;import javax.swing.JRadioButtonMenuItem;import javax.swing.JTextField;public class Calucator extends

3、 JFrame private JTextField tf;private JPanel panel1, panel2, panel3, panel4;private JMenuBar myBar;private JMenu menu1, menu2, menu3;private JMenuItem editItem1, editItem2, help1, help2, help3;private JRadioButtonMenuItem seeItem1, seeItem2;/单选框private JCheckBoxMenuItem seeItem3;/复选框private ButtonGr

4、oup bgb;private String back;private boolean IfResult = true, flag = false;private String oper = "="private double result = 0;private Num numActionListener;private DecimalFormat df;public Calucator()super("科学计算器");/设置标题栏df = new DecimalFormat("#.#");/保留四位小数this.setLayout

5、(new BorderLayout(10, 5);panel1 = new JPanel(new GridLayout(1, 3, 10, 10);panel2 = new JPanel(new GridLayout(5, 6, 5, 5);/5行6列panel3 = new JPanel(new GridLayout(5, 1, 5, 5);panel4 = new JPanel(new BorderLayout(5, 5);/* * 菜单栏 */myBar = new JMenuBar();menu1 = new JMenu("编辑(E)");menu2 = new J

6、Menu("查看(V)");menu3 = new JMenu("帮助(H)");menu1.setFont(new Font("宋体", Font.PLAIN, 12);menu2.setFont(new Font("宋体", Font.PLAIN, 12);menu3.setFont(new Font("宋体", Font.PLAIN, 12);/* * 编辑栏 */editItem1 = new JMenuItem("复制(C) Ctrl+C");editItem2 =

7、 new JMenuItem("粘贴(P) Ctrl+V");editItem1.setFont(new Font("宋体",Font.PLAIN,12);editItem2.setFont(new Font("宋体",Font.PLAIN,12);/* * 查看栏 */seeItem1 = new JRadioButtonMenuItem("科学型(T)");seeItem2 = new JRadioButtonMenuItem("标准型(S)");seeItem3 = new JCheckB

8、oxMenuItem("数字分组(I)");seeItem1.setFont(new Font("宋体",Font.PLAIN,12);seeItem2.setFont(new Font("宋体",Font.PLAIN,12);seeItem3.setFont(new Font("宋体",Font.PLAIN,12);/* * 帮助栏 */help1 = new JMenuItem("帮助主题(H)");help2 = new JMenuItem("关于计算器(A)");he

9、lp1.setFont(new Font("宋体",Font.PLAIN,12);help2.setFont(new Font("宋体",Font.PLAIN,12);bgb = new ButtonGroup();/选项组menu1.add(editItem1);menu1.add(editItem2);menu2.add(seeItem1);menu2.add(seeItem2);menu2.addSeparator();/添加一条分割线menu2.add(seeItem3);menu3.add(help1);menu3.addSeparator()

10、;/添加一条分割线menu3.add(help2);myBar.add(menu1);myBar.add(menu2);myBar.add(menu3);this.setJMenuBar(myBar);numActionListener = new Num();/实现数字监听/* * 文本域，即为计算器的屏幕显示区域 */tf = new JTextField();tf.setEditable(false);/文本区域不可编辑tf.setBackground(Color.white);/文本区域的背景色tf.setHorizontalAlignment(JTextField.RIGHT);/文

11、字右对齐tf.setText("0");tf.setBorder(BorderFactory.createLoweredBevelBorder();init();/对计算器进行初始化/* * 初始化操作 * 添加按钮 */private void init()addButton(panel1, "Backspace", new Clear(), Color.red);addButton(panel1, "CE", new Clear(), Color.red);addButton(panel1, "C", new

12、Clear(), Color.red);addButton(panel2, "1/x", new Signs(), Color.magenta);addButton(panel2, "log", new Signs(), Color.magenta);addButton(panel2, "7", numActionListener, Color.blue);addButton(panel2, "8", numActionListener, Color.blue);addButton(panel2, "9&

13、quot;, numActionListener, Color.blue);addButton(panel2, "÷", new Signs(), Color.red);addButton(panel2, "n!", new Signs(), Color.magenta);addButton(panel2, "sqrt", new Signs(), Color.magenta);addButton(panel2, "4", numActionListener, Color.blue);addButton(

14、panel2, "5", numActionListener, Color.blue);addButton(panel2, "6", numActionListener, Color.blue);addButton(panel2, "×", new Signs(), Color.red);addButton(panel2, "sin", new Signs(), Color.magenta);addButton(panel2, "x2", new Signs(), Color.mage

15、nta);addButton(panel2, "1", numActionListener, Color.blue);addButton(panel2, "2", numActionListener, Color.blue);addButton(panel2, "3", numActionListener, Color.blue);addButton(panel2, "-", new Signs(), Color.red);addButton(panel2, "cos", new Signs()

16、, Color.magenta);addButton(panel2, "x3", new Signs(), Color.magenta);addButton(panel2, "0", numActionListener, Color.blue);addButton(panel2, "-/+", new Clear(), Color.blue);addButton(panel2, ".", new Dot(), Color.blue);addButton(panel2, "+", new Sign

17、s(), Color.red);addButton(panel2, "tan", new Signs(), Color.magenta);addButton(panel2, "%", new Signs(), Color.magenta);addButton(panel2, "", numActionListener, Color.orange);addButton(panel2, "e", numActionListener, Color.orange);addButton(panel2, ""

18、;, new Signs(), Color.orange);addButton(panel2, "=", new Signs(), Color.red);JButton btns = new JButton("计算器");btns.setBorder(BorderFactory.createLoweredBevelBorder();btns.setEnabled(false);/按钮不可操作btns.setPreferredSize(new Dimension(20, 20);panel3.add(btns);/加入按钮addButton(panel3,

19、 "MC", null, Color.red);addButton(panel3, "MR", null, Color.red);addButton(panel3, "MS", null, Color.red);addButton(panel3, "M+", null, Color.red);panel4.add(panel1, BorderLayout.NORTH);panel4.add(panel2, BorderLayout.CENTER);this.add(tf, BorderLayout.NORTH);t

20、his.add(panel3, BorderLayout.WEST);this.add(panel4);pack();this.setResizable(false);/窗口不可改变大小this.setLocation(300, 200);this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);/* * 统一设置按钮的的使用方式 * param panel * param name * param action * param color */private void addButton(JPanel panel, String name, Ac

21、tionListener action, Color color)JButton bt = new JButton(name);panel.add(bt);/在面板上增加按钮bt.setForeground(color);/设置前景（字体）颜色bt.addActionListener(action);/增加监听事件/* * 计算器的基础操作（+ - × ÷） * param x */private void getResult (double x)if(oper = "+")result += x;else if(oper = "-"

22、)result -= x;else if(oper = "×")result *= x;else if(oper = "÷")result /= x;else if(oper = "=")result = x;tf.setText(df.format(result);/* * 运算符号的事件监听 */class Signs implements ActionListenerpublic void actionPerformed(ActionEvent e) /* * 用ActionEvent对象的getAction

23、Command()方法 * 取得与引发事件对象相关的字符串 */String str = e.getActionCommand();/* sqrt求平方根 */if(str.equals("sqrt")double i = Double.parseDouble(tf.getText();if(i>=0)/* * String.valueOf() 转换为字符串 * df.format() 按要求保留四位小数 * Math.sqrt() 求算数平方根 */tf.setText(String.valueOf(df.format(Math.sqrt(i);elsetf.set

24、Text("负数不能开平方根");/* log求常用对数 */else if(str.equals("log")double i = Double.parseDouble(tf.getText();if(i>0)tf.setText(String.valueOf(df.format(Math.log(i);elsetf.setText("负数不能求对数");/* %求百分比 */else if(str.equals("%")tf.setText(df.format(Double.parseDouble(tf.

25、getText() / 100);/* 1/x求倒数 */else if(str.equals("1/x")if(Double.parseDouble(tf.getText() = 0)tf.setText("除数不能为零");elsetf.setText(df.format(1 / Double.parseDouble(tf.getText();/* sin求正弦函数 */else if(str.equals("sin")double i = Double.parseDouble(tf.getText();tf.setText(St

26、ring.valueOf(df.format(Math.sin(i);/* cos求余弦函数 */else if(str.equals("cos")double i = Double.parseDouble(tf.getText();tf.setText(String.valueOf(df.format(Math.cos(i);/* tan求正切函数 */else if(str.equals("tan")double i = Double.parseDouble(tf.getText();tf.setText(String.valueOf(df.form

27、at(Math.tan(i);/* n!求阶乘 */else if(str.equals("n!")double i = Double.parseDouble(tf.getText();if(i%2=0)|(i%2=1)/判断为整数放进行阶乘操作int j = (int)i;/强制类型转换int result=1;for(int k=1;k<=j;k+)result *= k;tf.setText(String.valueOf(result);elsetf.setText("无法进行阶乘");/* x2求平方 */else if(str.equal

28、s("x2")double i = Double.parseDouble(tf.getText();tf.setText(String.valueOf(df.format(i*i);/* x3求立方 */else if(str.equals("x3")double i = Double.parseDouble(tf.getText();tf.setText(String.valueOf(df.format(i*i*i);/* 角度转换 */* * 将角度值转换成弧度值，方便三角函数的计算 */else if(str.equals(""

29、)double i = Double.parseDouble(tf.getText();tf.setText(String.valueOf(i/180*Math.PI);elseif(flag)IfResult = false;if(IfResult)oper = str;else getResult(Double.parseDouble(tf.getText();oper = str;IfResult = true;/* * 清除按钮的事件监听 */class Clear implements ActionListenerpublic void actionPerformed(ActionE

30、vent e) /* * 用ActionEvent对象的getActionCommand()方法 * 取得与引发事件对象相关的字符串 */String str = e.getActionCommand();if(str = "C")tf.setText("0");IfResult = true;result = 0;else if(str = "-/+")double i = 0 - Double.parseDouble(tf.getText().trim();tf.setText(df.format(i);else if(str = "Backspace")if(Double.parseDouble(tf.getText() > 0)if(tf.getText().length() > 1)tf.setText(tf.getText().substring(0, tf.get