ji.java

java编写计算器的源代码,会经常用得到

import java.awt.*;
import java.awt.event.*;
public class Ji{
    static Frame vedio=new Frame("TextVedio");
    static Frame btn=new Frame("Button");
    static Button i1=new Button("1");
    static Button i2=new Button("2");
    static Button i3=new Button("3");
    static Button i4=new Button("4");
    static Button i5=new Button("5");
    static Button i6=new Button("6");
    static Button i7=new Button("7");
    static Button i8=new Button("8");
    static Button i9=new Button("9");
    static Button i0=new Button("0");
    static Button plus=new Button("+");
    static Button minus=new Button("-");
    static Button chen=new Button("X");
    static Button chu=new Button("/");
    static Button equal=new Button("=");
    static Button ac=new Button("AC");
    static TextField tf=new TextField("0");
    static String tmp;
    static int to;
    public static void main(String args[]){
        btn.add(i1);
        btn.add(i2);
        btn.add(i3);
        btn.add(plus);
        btn.add(i4);
        btn.add(i5);
        btn.add(i6);
        btn.add(minus);
        btn.add(i7);
        btn.add(i8);
        btn.add(i9);
        btn.add(chen);
        btn.add(ac);
        btn.add(i0);
        btn.add(equal);
        btn.add(chu);
        btn.setSize(400,400);
        btn.setLayout(new GridLayout(4,4));
        btn.show();
        
        vedio.add(tf);
        vedio.setSize(500,70);
        vedio.show();
        btn.addWindowListener(new java.awt.event.WindowListener(){
            public void windowClosing(WindowEvent e){System.exit(0);}
            public void windowClosed(WindowEvent e){ }
            public void windowOpened(WindowEvent e){ }
            public void windowIconified(WindowEvent e){ }
            public void windowDeiconified(WindowEvent e){ }
            public void windowActivated(WindowEvent e){ }
            public void windowDeactivated(WindowEvent e){ }
        });
        vedio.addWindowListener(new java.awt.event.WindowListener(){
            public void windowClosing(WindowEvent e){System.exit(0);}
            public void windowClosed(WindowEvent e){ }
            public void windowOpened(WindowEvent e){ }
            public void windowIconified(WindowEvent e){ }
            public void windowDeiconified(WindowEvent e){ }
            public void windowActivated(WindowEvent e){ }
            public void windowDeactivated(WindowEvent e){ }
        });
        i1.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("1");
            }
        });
        i2.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("2");
            }
        });
        i3.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("3");
            }
        });
        i4.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("4");
            }
        });
        
        i5.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("5");
            }
        }); 
        i6.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("6");
            }
        });
       i7.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("7");
            }
        });  
        i8.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("8");
            }
        });
        i9.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("9");
            }
        });
        i0.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addString("0");
            }
        });
        plus.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addo("+");
            }
        });
        minus.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addo("-");
            }
        });
        chen.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addo("X");
            }
        });
        chu.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                addo("/");
            }
        });
        equal.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                doequals();
            }
        });
        ac.addActionListener(new ActionListener(){
            public void actionPerformed(ActionEvent e){
                tf.setText("0");
            }
        });
    }
    public static void addString(String s){
        String temp=tf.getText();
        if(temp.equals("0")){
            tf.setText(s);
        }else{
            tf.setText(tf.getText()+s);
        }
    }
    public static void addo(String o){
        tmp=tf.getText();
        if(o.equals("+")){
            to=1;
        }else if(o.equals("-")){
            to=2;
        }else if(o.equals("X")){
            to=3;
        }else if(o.equals("/")){
            to=4;
        }
        tf.setText("");
    }
    public static void doequals(){
        try{
        String temp=tf.getText();
        double d1=Double.parseDouble(tmp);
        double d2=Double.parseDouble(temp);
        double sum=0;
        if(to==1){
            sum=d1+d2;
        }else if(to==2){
            sum=d1-d2;
        }else if(to==3){
            sum=d1*d2;
        }else if(to==4){
            sum=d1/d2;
        }
        tf.setText(Double.toString(sum));
        }catch(Exception e){
            tf.setText("It is not a Number!");
        }
    }
}