??????? 這是我初學Java時用Java編寫的小型計算器，現在看來，確實有點幼稚，不過，畢竟是自己寫的，放在這里，權作紀念吧，嘿嘿。
?????? 代碼如下：
import?java.awt.*;
import?java.awt.event.*;
public?class?Calculator?extends?Frame
{
?TextField?text?=?new?TextField(20);
?Panel?p=new?Panel();
?double?num;???????????//存放操作數
?String?op;
?double?result;????????//存放計算結果
?int?idx=0;????????????//用于退格鍵
?boolean?flag=false;//用于追加數字還是重新顯示
?boolean?dbClick=false;//是否連按"="號
?public?Calculator()
?{
??super("簡易計算器");
??String[]?name??={"退格","CE","C","/","7","8","9","*","4","5","6","-",
??????"1","2","3","+","0","+/-",".","="};??????
??Button[]?button=?new??Button[name.length];
??add(text,"North");
??text.setFont(new?Font("宋體",Font.BOLD,20));
??text.setText("0.0");
??text.setEditable(false);
??text.setFocusable(false);
??
??p.setLayout(new?GridLayout(5,4,2,2));??
??for?(int?i=0;i<name.length;i++)
??{
???button[i]=new?Button(name[i]);
???if(i<=3||i==7||i==11||i==15||i==19)
???{//設置按鈕前景色
????button[i].setForeground(Color.red);
???}
???else
???{
????button[i].setForeground(Color.blue);
???}
???button[i].setFont(new?Font("宋體",Font.BOLD,15));
???button[i].addActionListener(new?MyActionListener());//添加監聽器
???p.add(button[i]);?
??}??
??add(p,"South");
??setSize(250,200);
??this.setLocation(300,300);
??this.setResizable(false);//窗體不可改變大小??
??addWindowListener(new?WindowAdapter()
??{
???public?void?windowClosing(WindowEvent?e)
???{
????System.exit(0);
???}
??});??
??this.setVisible(true);
?}
?class?MyActionListener?implements?ActionListener
?{
??public?void?actionPerformed(ActionEvent?e)
??{
???String?input=text.getText();
???String?str=e.getActionCommand();
???if(isNum(str))
???{
????if(!flag)
????{
?????if(input!=""&&!input.equals("0.0")&&!input.equals("0"))
?????{
??????text.setText(input+str);
?????}
?????else
?????{?
??????text.setText(str);
?????}
????}
????else
????{?????
?????text.setText(str);
????}
????flag=false;???
???}
??????else?if(str.equals("+")||str.equals("-")||str.equals("*")||str.equals("/"))
???{
????result=Double.parseDouble(input);
????op=str;
????flag=true;
????dbClick=false;
???}
??????if(str.equals("="))
???{
????if(dbClick==false)
????{
?????num=Double.parseDouble(input);
????}???????????
????if(op.equals("+"))
????{
?????result+=num;
????}
????if(op.equals("-"))
????{
?????result-=num;
????}
????if(op.equals("*"))
????{
?????result*=num;
????}
????if(op.equals("/"))
????{
?????if(num!=0.0)
?????{
??????result/=num;?????
?????}????????
????}
????text.setText(""+result);
????flag=false;
????dbClick=true;
???}
???if(str.equals("CE"))
???{
????text.setText("0.0");????
????num=0;???
???}
???if(str.equals(".")&&input.indexOf(".")<0)
???{
????text.setText(input+".");????
???}
???if(str.equals("+/-"))
???{
????double?m?=?Double.parseDouble(input);
????if(m!=0.0)
????{
?????text.setText(m*(-1)+"");
????}
???}
???if(str.equals("C"))
???{
????text.setText("0.0");
????flag=false;
????dbClick=false;
????result=0;
????num=0;
???}
???if(str.equals("退格"))
???{
????idx=input.length()-1;
????if(idx<0)
????{
?????return;
????}
????text.setText(input.substring(0,idx));
???}
???
??}
?}
?public?boolean?isNum(String?str)
?{
??if(str.equals("0")||str.equals("1")||str.equals("2")||str.equals("3")||str.equals("4")
???||str.equals("5")||str.equals("6")||str.equals("7")||str.equals("8")||str.equals("9"))
??{
???return?true;
??}
??else
??{
???return?false;
??}
?}
?public?static?void?main(String[]?args)
?{
??new?Calculator();
?}
}posted on 2006-04-15 00:52
南一郎 閱讀(973)
評論(1) 編輯 收藏