//frame版程序源代碼如下，疏漏之處，望批評指正。
//數字分組沒有編寫，科學型計算器沒有編寫，其他已經完善。
import java.awt.*;
import java.lang.*;
import javax.swing.*;
import javax.swing.event.*;
import java.awt.event.*;
import java.text.DecimalFormat;
public class Calculator
implements ActionListener { //導入動作監聽接口
//設計面板中的單位
JFrame frame;
JTextField textAnswer;
JPanel panel, panel1, panel2, panel3;
JMenuBar mainMenu;
JTextField textMemory;
JLabel labelMemSpace; //labelMemSpace單純做擺設，控制面板的形狀
JButton buttonBk, buttonCe, buttonC;
JButton button[];
JButton buttonMC, buttonMR, buttonMS, buttonMAdd;
JButton buttonDot, buttonAddAndSub, buttonAdd, buttonSub, buttonMul,
buttonDiv, buttonMod;
JButton buttonSqrt, buttonDao, buttonEqual;
JMenu editMenu, viewMenu, helpMenu;
JMenuItem copyItem, pasteItem, tItem, sItem, numberGroup, topHelp, aboutCal;
DecimalFormat df; //設置數據輸出精度
boolean clickable; //控制當前能否按鍵
double memoryd; //使用內存中存儲的數字
int memoryi;
double vard, answerd; //用來保存double型數據的中間值(vard)和最後結果(answerd)
short key = -1, prekey = -1; //key用來保存當前進行何種運算,prekey用來保存前次進行何種運算
String copy; //做復制用
JTextArea help; //幫助
JScrollPane scrollHelp;
//構造函數
public Calculator() {
clickable = true;
answerd = 0;
frame = new JFrame("計算器");
df = new DecimalFormat("0.##############"); //設置數據輸出精度(對於double型值)
textAnswer = new JTextField(15);
textAnswer.setText("");
textAnswer.setEditable(false);
textAnswer.setBackground(new Color(255, 255, 255));
panel = new JPanel();
frame.getContentPane().add(panel);
panel1 = new JPanel();
panel2 = new JPanel();
panel.setLayout(new BorderLayout());
//設計整個面板
mainMenu = new JMenuBar();
editMenu = new JMenu("編輯(E)");
viewMenu = new JMenu("查看(V)");
helpMenu = new JMenu("幫助(H)");
copyItem = new JMenuItem(" 復制(C) Ctrl+C");
copyItem.addActionListener(this);
pasteItem = new JMenuItem(" 粘貼(V) Ctrl+V");
pasteItem.addActionListener(this);
editMenu.add(copyItem);
editMenu.add(pasteItem);
tItem = new JMenuItem("●標准型(T)");
tItem.addActionListener(this);
sItem = new JMenuItem(" 科學型(S)");
sItem.addActionListener(this);
numberGroup = new JMenuItem(" 數字分組(I)");
numberGroup.addActionListener(this);
viewMenu.add(tItem);
viewMenu.add(sItem);
viewMenu.add(numberGroup);
topHelp = new JMenuItem(" 幫助主題(H)");
topHelp.addActionListener(this);
help = new JTextArea(5, 20);
scrollHelp = new JScrollPane(help);
help.setEditable(false);
help.append("執行簡單計算\n");
help.append("1. 鍵入計算的第一個數字。\n");
help.append("2. 單擊“+”執行加、“-”執行減、“*”執行乘或“/”執行除。\n");
help.append("3. 鍵入計算的下一個數字。\n");
help.append("4. 輸入所有剩余的運算符和數字。\n");
help.append("5. 單擊“=”。\n");
aboutCal = new JMenuItem(" 關於計算器(A)");
aboutCal.addActionListener(this);
helpMenu.add(topHelp);
helpMenu.add(aboutCal);
mainMenu.add(editMenu);
mainMenu.add(viewMenu);
mainMenu.add(helpMenu);
panel.add(mainMenu, BorderLayout.NORTH);
panel.add(textAnswer, BorderLayout.CENTER);
panel.add(panel1, BorderLayout.SOUTH);
panel1.setLayout(new BorderLayout());
textMemory = new JTextField(3);
textMemory.setEditable(false);
textMemory.setBackground(new Color(217, 217, 217));
labelMemSpace = new JLabel(" ");
buttonBk = new JButton("Backspace");
buttonBk.setForeground(new Color(255, 0, 0));
buttonCe = new JButton("CE");
buttonCe.setForeground(new Color(255, 0, 0));
buttonC = new JButton("C");
buttonC.setForeground(new Color(255, 0, 0));
buttonBk.addActionListener(this);
buttonCe.addActionListener(this);
buttonC.addActionListener(this);
panel1.add(panel2, BorderLayout.NORTH);
panel2.setLayout(new FlowLayout(FlowLayout.RIGHT));
panel2.add(textMemory);
panel2.add(labelMemSpace);
panel2.add(buttonBk);
panel2.add(buttonCe);
panel2.add(buttonC);
panel3 = new JPanel();
panel1.add(panel3, BorderLayout.CENTER);
button = new JButton[10];
for (int i = 0; i < button.length; i++) {
button[i] = new JButton(Integer.toString(i));
button[i].setForeground(new Color(0, 0, 255));
}
buttonMC = new JButton("MC");
buttonMC.setForeground(new Color(255, 0, 0));
buttonMR = new JButton("MR");
buttonMR.setForeground(new Color(255, 0, 0));
buttonMS = new JButton("MS");
buttonMS.setForeground(new Color(255, 0, 0));
buttonMAdd = new JButton("M+");
buttonMAdd.setForeground(new Color(255, 0, 0));
buttonDot = new JButton(".");
buttonDot.setForeground(new Color(0, 0, 255));
buttonAddAndSub = new JButton("+/-");
buttonAddAndSub.setForeground(new Color(0, 0, 255));
buttonAdd = new JButton("+");
buttonAdd.setForeground(new Color(255, 0, 0));
buttonSub = new JButton("-");
buttonSub.setForeground(new Color(255, 0, 0));
buttonMul = new JButton("*");
buttonMul.setForeground(new Color(255, 0, 0));
buttonDiv = new JButton("/");
buttonDiv.setForeground(new Color(255, 0, 0));
buttonMod = new JButton("%");
buttonMod.setForeground(new Color(0, 0, 255));
buttonSqrt = new JButton("sqrt");
buttonSqrt.setForeground(new Color(0, 0, 255));
buttonDao = new JButton("1/x");
buttonDao.setForeground(new Color(0, 0, 255));
buttonEqual = new JButton("=");
buttonEqual.setForeground(new Color(255, 0, 0));
//將所有行為與監聽綁定
panel3.setLayout(new GridLayout(4, 6));
panel3.add(buttonMC);
buttonMC.addActionListener(this);
panel3.add(button[7]);
button[7].addActionListener(this);
panel3.add(button[8]);
button[8].addActionListener(this);
panel3.add(button[9]);
button[9].addActionListener(this);
panel3.add(buttonDiv);
buttonDiv.addActionListener(this);
panel3.add(buttonSqrt);
buttonSqrt.addActionListener(this);
panel3.add(buttonMR);
buttonMR.addActionListener(this);
panel3.add(button[4]);
button[4].addActionListener(this);
panel3.add(button[5]);
button[5].addActionListener(this);
panel3.add(button[6]);
button[6].addActionListener(this);
panel3.add(buttonMul);
buttonMul.addActionListener(this);
panel3.add(buttonMod);
buttonMod.addActionListener(this);
panel3.add(buttonMS);
buttonMS.addActionListener(this);
panel3.add(button[1]);
button[1].addActionListener(this);
panel3.add(button[2]);
button[2].addActionListener(this);
panel3.add(button[3]);
button[3].addActionListener(this);
panel3.add(buttonSub);
buttonSub.addActionListener(this);
panel3.add(buttonDao);
buttonDao.addActionListener(this);
panel3.add(buttonMAdd);
buttonMAdd.addActionListener(this);
panel3.add(button[0]);
button[0].addActionListener(this);
panel3.add(buttonAddAndSub);
buttonAddAndSub.addActionListener(this);
panel3.add(buttonDot);
buttonDot.addActionListener(this);
panel3.add(buttonAdd);
buttonAdd.addActionListener(this);
panel3.add(buttonEqual);
buttonEqual.addActionListener(this);
frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
frame.pack();
frame.show();
}
//設置各個按鈕行為
public void actionPerformed(ActionEvent event) {
boolean sign = false; //判斷是否是double型數參與運算，是為true，不是為false
Object temp = event.getSource();
try {
//如果按下數據按鈕，將按下的按鈕代表的數據插入的當前文本框字符串之後
for (int i = 0; i <= 9; i++)
if (temp == button[i] && clickable == true)
textAnswer.setText(textAnswer.getText() + Integer.toString(i));
//按下'.'按鈕時，判斷當前文本框內字符串中含不含'.'，如果已含，則不允許再插入'.'
if (temp == buttonDot && clickable == true) {
boolean isDot = false;
if (textAnswer.getText().length() == 0)
isDot = true;
for (int i = 0; i < textAnswer.getText().length(); i++)
if ('.' == textAnswer.getText().charAt(i)) {
isDot = true;
break;
}
if (isDot == false)
textAnswer.setText(textAnswer.getText() + ".");
}
if ( (temp == buttonAdd || temp == buttonSub || temp == buttonMul ||
temp == buttonDiv) && clickable == true) {
//'+'操作
if (temp == buttonAdd) {
switch (prekey) {
case 0:
answerd += Double.parseDouble(textAnswer.getText());
break;
case 1:
answerd -= Double.parseDouble(textAnswer.getText());
break;
case 2:
answerd *= Double.parseDouble(textAnswer.getText());
break;
case 3:
if (Double.parseDouble(textAnswer.getText()) == 0) {
textAnswer.setText("除數不能為零");
clickable = false;
}
else
answerd /= Double.parseDouble(textAnswer.getText());
break;
default:
answerd = Double.parseDouble(textAnswer.getText());
}
textAnswer.setText("");
prekey = key = 0;
}
//'-'操作
if (temp == buttonSub) {
switch (prekey) {
case 0:
answerd += Double.parseDouble(textAnswer.getText());
break;
case 1:
answerd -= Double.parseDouble(textAnswer.getText());
break;
case 2:
answerd *= Double.parseDouble(textAnswer.getText());
break;
case 3:
if (Double.parseDouble(textAnswer.getText()) == 0) {
textAnswer.setText("除數不能為零");
clickable = false;
}
else
answerd /= Double.parseDouble(textAnswer.getText());
break;
default:
answerd = Double.parseDouble(textAnswer.getText());
}
textAnswer.setText("");
prekey = key = 1;
}
//'*'操作
if (temp == buttonMul) {
switch (prekey) {
case 0:
answerd += Double.parseDouble(textAnswer.getText());
break;
case 1:
answerd -= Double.parseDouble(textAnswer.getText());
break;
case 2:
answerd *= Double.parseDouble(textAnswer.getText());
break;
case 3:
if (Double.parseDouble(textAnswer.getText()) == 0) {
textAnswer.setText("除數不能為零");
clickable = false;
}
else
answerd /= Double.parseDouble(textAnswer.getText());
break;
default:
answerd = Double.parseDouble(textAnswer.getText());
}
textAnswer.setText("");
prekey = key = 2;
}
//'/'操作
if (temp == buttonDiv) {
switch (prekey) {
case 0:
answerd += Double.parseDouble(textAnswer.getText());
break;
case 1:
answerd -= Double.parseDouble(textAnswer.getText());
break;
case 2:
answerd *= Double.parseDouble(textAnswer.getText());
break;
case 3:
if (Double.parseDouble(textAnswer.getText()) == 0) {
textAnswer.setText("除數不能為零");
clickable = false;
}
else
answerd /= Double.parseDouble(textAnswer.getText());
break;
default:
answerd = Double.parseDouble(textAnswer.getText());
}
textAnswer.setText("");
prekey = key = 3;
}
}
//'='操作
if (temp == buttonEqual && clickable == true) {
//如果連續按'=',則進行連續運算
if (prekey == 5) {
if (key == 0) {
answerd += vard;
textAnswer.setText(df.format(answerd));
}
if (key == 1) {
answerd -= vard;
textAnswer.setText(df.format(answerd));
}
if (key == 2) {
answerd *= vard;
textAnswer.setText(df.format(answerd));
}
if (key == 3) {
if (Double.parseDouble(textAnswer.getText()) == 0) {
textAnswer.setText("除數不能為零");
clickable = false;
}
else {
answerd /= vard;
textAnswer.setText(df.format(answerd));
}
}
}
else {
vard = Double.parseDouble(textAnswer.getText());
if (key == 0) {
prekey = -1;
answerd += Double.parseDouble(textAnswer.getText());
textAnswer.setText(df.format(answerd));
}
if (key == 1) {
prekey = -1;
answerd -= Double.parseDouble(textAnswer.getText());
textAnswer.setText(df.format(answerd));
}
if (key == 2) {
prekey = -1;
answerd *= Double.parseDouble(textAnswer.getText());
textAnswer.setText(df.format(answerd));
}
if (key == 3) {
prekey = -1;
if (Double.parseDouble(textAnswer.getText()) == 0) {
textAnswer.setText("除數不能為零");
clickable = false;
}
else {
answerd /= Double.parseDouble(textAnswer.getText());
textAnswer.setText(df.format(answerd));
}
}
}
prekey = 5;
}
//'%'操作，對第二個操作數除以100
if (temp == buttonMod && clickable == true) {
if (answerd == 0) {
String s = textAnswer.getText();
textAnswer.setText(s);
}
else {
boolean isDot = false;
for (int i = 0; i < textAnswer.getText().length(); i++)
if ('.' == textAnswer.getText().charAt(i)) {
isDot = true;
break;
}
//如果是double數，除100
if (isDot == true) {
double dtemp = Double.parseDouble(textAnswer.getText());
dtemp = dtemp / 100.0;
textAnswer.setText(Double.toString(dtemp));
}
else {
//如果是int數但能被100整除，則去掉末尾兩個零
if (Integer.parseInt(textAnswer.getText()) % 100 == 0) {
int itemp = Integer.parseInt(textAnswer.getText());
itemp /= 100;
textAnswer.setText(Integer.toString(itemp));
}
//如果是int數，但不能被100整除，則按double數處理
else {
double dtemp = Double.parseDouble(textAnswer.getText());
dtemp = dtemp / 100.0;
textAnswer.setText(Double.toString(dtemp));
}
}
}
}
//開根號運算
if (temp == buttonSqrt && clickable == true) {
String s = textAnswer.getText();
if (s.charAt(0) == '-') {
textAnswer.setText("負數不能開根號");
clickable = false;
}
else
textAnswer.setText(Double.toString(java.lang.Math.sqrt(Double.
parseDouble(textAnswer.getText()))));
}
//倒數運算
if (temp == buttonDao && clickable == true) {
if (textAnswer.getText().charAt(0) == '0' &&
textAnswer.getText().length() == 1) {
textAnswer.setText("零不能求倒數");
clickable = false;
}
else {
boolean isDec = true;
int i, j, k;
String s = Double.toString(1 / Double.parseDouble(textAnswer.getText()));
for (i = 0; i < s.length(); i++)
if (s.charAt(i) == '.')
break;
for (j = i + 1; j < s.length(); j++)
if (s.charAt(j) != '0') {
isDec = false;
break;
}
if (isDec == true) {
String stemp = "";
for (k = 0; k < i; k++)
stemp += s.charAt(k);
textAnswer.setText(stemp);
}
else
textAnswer.setText(s);
}
}
//按下'+/-'按鈕時處理
if (temp == buttonAddAndSub && clickable == true) {
boolean isNumber = true;
String s = textAnswer.getText();
for (int i = 0; i < s.length(); i++)
if (! (s.charAt(i) >= '0' && s.charAt(i) <= '9' || s.charAt(i) == '.' ||
s.charAt(i) == '-')) {
isNumber = false;
break;
}
if (isNumber == true) {
//如果當前字符串首字母有'-'號,代表現在是個負數,再按下時,則將首符號去掉
if (s.charAt(0) == '-') {
textAnswer.setText("");
for (int i = 1; i < s.length(); i++) {
char a = s.charAt(i);
textAnswer.setText(textAnswer.getText() + a);
}
}
//如果當前字符串第一個字符不是符號，則添加一個符號在首字母處
else
textAnswer.setText('-' + s);
}
}
//計算器有關內存操作
//'MC'的操作，將內存清0
if (temp == buttonMC && clickable == true) {
memoryd = memoryi = 0;
textMemory.setText("");
}
//'MS'的操作，將當前文本框內容保存入內存，顯示'M'
if (temp == buttonMS && clickable == true) {
boolean isDot = false;
textMemory.setText(" M");
for (int i = 0; i < textAnswer.getText().length(); i++)
if ('.' == textAnswer.getText().charAt(i)) {
isDot = true;
break;
}
//如果是double,則存入memoryd(double存儲器)
if (isDot == true) {
memoryd = Double.parseDouble(textAnswer.getText());
memoryi = 0; //保證存儲器中存放最新的值
}
//如果是int,則存入memoryi(int存儲器)
else {
memoryi = Integer.parseInt(textAnswer.getText());
memoryd = 0; //保證存儲器中存放最新的值
}
}
//'MR'的操作，將存儲器中的信息輸出
if (temp == buttonMR && clickable == true) {
if (memoryd != 0)
textAnswer.setText(Double.toString(memoryd));
if (memoryi != 0)
textAnswer.setText(Integer.toString(memoryi));
}
//'M+'的功能，將當前文本框裡的數據和存儲器中數據相加後，再存入存儲器
if (temp == buttonMAdd && clickable == true) {
boolean isDot = false;
for (int i = 0; i < textAnswer.getText().length(); i++)
if ('.' == textAnswer.getText().charAt(i)) {
isDot = true;
break;
}
if (memoryi != 0) { //存儲中是一個int型數
if (isDot == false) //被加數是一個int型數---www.bianceng.cn
memoryi += Integer.parseInt(textAnswer.getText());
else { //被加數是一個double型數，則將int存儲器中數傳入double存儲器與當前數相加，int存儲器清零
memoryd = memoryi + Double.parseDouble(textAnswer.getText());
memoryi = 0;
}
}
else
memoryd += Double.parseDouble(textAnswer.getText());
}
//按下'Backspace'鍵，利用循環將當前字符串中的最後一個字母刪除
if (temp == buttonBk && clickable == true) {
String s = textAnswer.getText();
textAnswer.setText("");
for (int i = 0; i < s.length() - 1; i++) {
char a = s.charAt(i);
textAnswer.setText(textAnswer.getText() + a);
}
}
//按下'CE'按鈕，將當前文本框內數據清除
if (temp == buttonCe) {
textAnswer.setText("");
clickable = true;
}
//按下'C'按鈕，文本框內數據清除，同時var,answer清0
if (temp == buttonC) {
vard = answerd = 0;
textAnswer.setText("");
clickable = true;
}
//按下'復制'菜單欄
if (temp == copyItem) {
copy = textAnswer.getText();
}
//按下'粘貼'菜單欄
if (temp == pasteItem) {
textAnswer.setText(copy);
}
if (temp == sItem) {
JOptionPane.showMessageDialog(panel, "當前是標准型計算器，\n科學型計算器有待更新。");
}
//按下'幫助主題'菜單欄
if (temp == topHelp) {
JOptionPane.showMessageDialog(panel, scrollHelp);
}
//按下'數字分組'菜單欄
if (temp == numberGroup) {
if (numberGroup.getText().compareTo(" 數字分組(I)") == 0)
numberGroup.setText("√數字分組(I)");
else
numberGroup.setText(" 數字分組(I)");
}
//按下'關於'菜單欄
if (temp == aboutCal) {
JOptionPane.showMessageDialog(panel, "計算器1.00版\n開發者：樓競");
}
}
//輸入中如果有操作非法，比如按下兩次'+'，捕獲異常
catch (Exception e) {
textAnswer.setText("操作非法");
clickable = false;
}
}
//主函數
public static void main(String args[]) {
new Calculator();
}
}
