计算器

[java]代码库

/**
 * 计算器
 * @author 
 *
 */
public class Calculator extends JFrame implements ActionListener{
     
    //定义创建组件
    JTextField t=new JTextField(20);
    JButton[] b=new JButton[27];
    String[] s={"Backspace","CE","C",
                "MC","7","8","9","/","sqrt",
                "MR","4","5","6","*","%",
                "MS","1","2","3","-","1/x",
                "M+","0","+/-",".","+","="
                };
    JMenuBar jmb = new JMenuBar();
    JMenu jm1 = new JMenu("编辑(E)");
    JMenu jm2 = new JMenu("查看(V)");
    JMenu jm3 = new JMenu("帮助(H)");
    JMenuItem jmi1 = new JMenuItem("复制(C)");
    JMenuItem jmi2 = new JMenuItem("粘贴(P)");
    public Calculator() {
         
        this.setLayout(null);
        this.add(t);
        t.setHorizontalAlignment(JTextField.RIGHT);
        t.setEditable(false);
        t.setBounds(10,10,400,30);
         
        //添加按钮，同时注册监听
        for(int i=0;i<27;i++){
            b[i]=new JButton(s[i]);
            b[i].addActionListener(this);//注册监听
            b[i].setActionCommand(s[i]);
            this.add(b[i]);
        }
         
        //下面设置各个按钮之间的距离以及按钮的大小
        //前三个按钮设置为大小100，30，间距为10
        for(int i=0;i<3;i++){
            b[i].setBounds(90+110*i,50,100,30);
        }
         
        //剩余的按钮大小相同，只是间距有所不同
        int n=3;
        for(int i=0;i<4;i++){
            for(int j=0;j<6;j++){
                if((n-3)%6==0){
                    b[n].setBounds(10,90+35*i,60,30);
                }else{
                    b[n].setBounds(90+65*(j-1),90+35*i,60,30);
                }
                n++;
            }
        }
         
      //设置菜单
        this.setJMenuBar(jmb);
        jmb.add(jm1);
        jmb.add(jm2);
        jmb.add(jm3);
        jmi1.setMnemonic('C');
        jmi1.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C,InputEvent.CTRL_MASK));
        jmi2.setMnemonic('V');
        jmi2.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_V,InputEvent.CTRL_MASK));
        jm1.add(jmi1);
        jm1.add(jmi2);
        jmi1.addActionListener(this);//注册菜单监听
        jmi2.addActionListener(this);
        jmi1.setActionCommand("copy");
        jmi2.setActionCommand("paste");
      //设置窗体
        this.setTitle("计算器");
        ImageIcon icon = new ImageIcon("images/jisuan.jpg");
        this.setIconImage(icon.getImage());
        this.setSize(430,290);
        this.setLocation(200,200);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setResizable(false);
        this.setVisible(true);
    }
     
    public static void main(String[] args) {
        new Calculator();
    }
 
    String text[] = {"",""} ;
    String showString = "";//要显示的字符串
    int dotCount = 0;//点击小数点的次数
    int j = 0;//用来表示是第几个操作数
    int op = -1; //操作类型，0:/;1:*;2:-;3:+;4:%
    int flag = 0;
    String copyedString = "";
    @Override
    public void actionPerformed(ActionEvent e) {
        String comand = e.getActionCommand();
        if("copy".equals(comand)){
            copyedString =  t.getText();
        }
        if("paste".equals(comand)){
            if(!("".equals(copyedString))){
                showString = copyedString;
                text[j] = copyedString;
            }
        }
        for(int i = 4; i<7; i++){ //点击7、8、9
            if(s[i].equals(comand)) text[j] += s[i];
            showString = text[j];
        }
        for(int i = 10; i<13; i++){//点击4、5、6
            if(s[i].equals(comand)) text[j] += s[i];
            showString = text[j];
        }
        for(int i = 16; i<19; i++){//点击1、2、3
            if(s[i].equals(comand)) text[j] += s[i];
            showString = text[j];
        }
        if(s[22].equals(comand)) {//点击0
            text[j] += s[22];
            showString = text[j];
        }
        if(s[24].equals(comand)){ //点击".",只允许点一次，点第二次不给反应
            if(dotCount == 0) {
                text[j] += s[24];
                showString = text[j];
                dotCount ++;
            }
        }
        if(s[7].equals(comand)){//点击"/"
                showString = operator();
                text[0] = showString;
                text[1] = "";
                op = 0;
                j = 1;//下面要换成text[1]来记录第二个操作数
        }
        if(s[13].equals(comand)){//点击"*",只能点一次
                showString = operator();
                text[0] = showString;
                text[1] = "";
                op = 1;
                j = 1;//下面要换成text[1]来记录第二个操作数
        }
        if(s[19].equals(comand)){//点击"-",只能点一次
                showString = operator();
                text[0] = showString;
                text[1] = "";
                op = 2;
                j = 1;//下面要换成text[1]来记录第二个操作数
        }
        if(s[25].equals(comand)){//点击"+",只能点一次
                showString = operator();
                text[0] = showString;
                text[1] = "";
                op = 3;
                j = 1;//下面要换成text[1]来记录第二个操作数
        }
        if(s[14].equals(comand)){//点击%
            if(j==0) {
                op = 4;
                j = 1;
            }
        }
        if(s[0].equals(comand)){//点击Backspace
            int len = text[j].length();
            if(len > 0){
                text[j] = text[j].substring(0,text[j].length()-1);
                showString = text[j];
            }
        }
        if(s[2].equals(comand)){//点击c
                text[j] = "";
                showString = "";
        }
        if(s[23].equals(comand)){//点击+/-
            if(flag == 0){
                text[j] = "-"+text[j];
                showString = text[j];
                flag = 1;
            }else if(flag==1){
                text[j] = showString.substring(1,showString.length());
                showString = text[j];
                flag = 0;
            }
            System.out.println("flag===="+flag);
        }
        if(s[26].equals(comand)){//点击=
            showString = operator();
        }
        if(s[1].equals(comand)){//点击CE
            //此处直接将所有的数据全部恢复初始值，同时将文本框中的数值清空
            text[0] = "";
            text[1] = "";
            t.setText("");
            showString = "";
            dotCount = 0;
            op = -1;
            j = 0;
        }
        if(s[20].equals(comand)){//点击1/x
            if(!("".equals(text[j]))){
                double num = Double.parseDouble(text[j]);
                num = 1/num;
                text[j] = num+"";
                showString = num+"";
            }
        }
        if(s[8].equals(comand)){//点击sqrt
            if(!("".equals(text[j]))){
                double num = Double.parseDouble(text[j]);
                num = Math.sqrt(num);
                text[j] = dealResult(num+"");
                showString = text[j];
            }
        }
 
        t.setText(showString);
    }
     
    public String operator(){//进行计算
        if("".equals(text[1]) || "".equals(text[0])){
            return text[0];
        }
        double op1 = Double.parseDouble(text[0]);//得到第一个操作数
        double op2 = Double.parseDouble(text[1]);//得到第二个操作数
        double result = 0.0;
        //进行计算
        switch (op) {
        case 0://除
            if(op2 != 0){//除法时第二操作数不能是0
                result = op1 / op2;
            }
            break;
        case 1://乘
            result = op1*op2;
            break;
        case 2://减
            result = op1-op2;
            break;
        case 3://加
            result = op1 + op2;
            break;
        case 4:
            int mu1 = (int)op1;
            int mu2 = (int)op2;
            if((op1 == mu1) && (op1 == mu2)){//整除需要两个操作数都是整数
                result = (int)op1%(int)op2;
                System.out.println("zhen");
            }else{
                result = op2;
            }
            break;
        default:
            break;
        }
        String resString = result+"";
        resString = dealResult(resString);
        return resString;
    }
     
    String dealResult(String resString){
        int dotpos = resString.indexOf(".");
        if(resString.substring(dotpos+1, resString.length()).equals("0")){
            resString = resString.substring(0,dotpos);
        }
        return resString;
    }
}