applet计算器.txt

用JAVA语言实现的Applet计算器

package moonmoon;

/**
 * 此处插入类型描述。
 * 创建日期：(2001-11-8 8:32:07)
 * @author：Administrator
 */
import java.awt.*; 
import java.awt.event.*; 
import java.lang.*; 
import javax.swing.*;
import java.applet.*;

public class Constant extends Applet implements ActionListener {


Button number0,number1,number2,number3,number4,number5,number6,number7,number8,number9; 
Button backspace,clear,point,oper_add,oper_sub,oper_mul,oper_div,sqrt,postive,reflect,abs,amount; 
TextField display; 
String s_operator1="",s; 
String s_operator2=""; 
boolean oper2_begin=false; 
boolean pointed=false; 
char pressoper; 
public Constant() 
{ 


setLayout(null); 
setSize(380,310); 
number0=new Button("0"); 
number1=new Button("1"); 
number2=new Button("2"); 
number3=new Button("3"); 
number4=new Button("4"); 
number5=new Button("5"); 
number6=new Button("6"); 
number7=new Button("7"); 
number8=new Button("8"); 
number9=new Button("9"); 
backspace=new Button("backspace"); 
clear=new Button("clear"); 
oper_add=new Button("+"); 
oper_sub=new Button("-"); 
oper_mul=new Button("x"); 
oper_div=new Button("/"); 
postive=new Button("+/-"); 
reflect=new Button("1/x"); 
abs=new Button("abs"); 
sqrt=new Button("sqrt"); 
point=new Button("."); 
amount=new Button("="); 
display=new TextField(""); 
display.setText("0.");
setBackground(new Color(126,165,192));
display.setBackground(new Color(69,157,222));
number0.setForeground(Color.black); 
number1.setForeground(Color.black); 
number2.setForeground(Color.black); 
number3.setForeground(Color.black); 
number4.setForeground(Color.black); 
number5.setForeground(Color.black); 
number6.setForeground(Color.black); 
number7.setForeground(Color.black); 
number8.setForeground(Color.black); 
number9.setForeground(Color.black); 
oper_add.setForeground(Color.black); 
oper_sub.setForeground(Color.black); 
oper_mul.setForeground(Color.black); 
oper_div.setForeground(Color.black); 
postive.setForeground(Color.black); 
reflect.setForeground(Color.black); 
abs.setForeground(Color.black); 
sqrt.setForeground(Color.black); 
point.setForeground(Color.black); 
amount.setForeground(Color.black); 
backspace.setForeground(Color.black); 
clear.setForeground(Color.black); 
add(display); 
add(backspace); 
add(clear); 
add(number7); 
add(number8); 
add(number9); 
add(oper_div); 
add(sqrt); 
add(number4); 
add(number5); 
add(number6); 
add(oper_mul); 
add(abs); 
add(number1); 
add(number2); 
add(number3); 
add(oper_sub); 
add(reflect); 
add(number0); 
add(postive); 
add(point); 
add(oper_add); 
add(amount); 
display.setBounds(50,60,290,30); 
backspace.setBounds(50,100,80,30); 
clear.setBounds(260,100,80,30); 
number7.setBounds(50,140,50,30); 
number8.setBounds(110,140,50,30); 
number9.setBounds(170,140,50,30); 
oper_div.setBounds(230,140,50,30); 
sqrt.setBounds(290,140,50,30); 
number4.setBounds(50,180,50,30); 
number5.setBounds(110,180,50,30); 
number6.setBounds(170,180,50,30); 
oper_mul.setBounds(230,180,50,30); 
abs.setBounds(290,180,50,30); 
number1.setBounds(50,220,50,30); 
number2.setBounds(110,220,50,30); 
number3.setBounds(170,220,50,30); 
oper_sub.setBounds(230,220,50,30); 
reflect.setBounds(290,220,50,30); 
number0.setBounds(50,260,50,30); 
postive.setBounds(110,260,50,30); 
point.setBounds(170,260,50,30); 
oper_add.setBounds(230,260,50,30); 
amount.setBounds(290,260,50,30); 
number0.addActionListener(this); 
number1.addActionListener(this); 
number2.addActionListener(this); 
number3.addActionListener(this); 
number4.addActionListener(this); 
number5.addActionListener(this); 
number6.addActionListener(this); 
number7.addActionListener(this); 
number8.addActionListener(this); 
number9.addActionListener(this); 
oper_add.addActionListener(this); 
oper_sub.addActionListener(this); 
oper_mul.addActionListener(this); 
oper_div.addActionListener(this); 
amount.addActionListener(this); 
point.addActionListener(this); 
abs.addActionListener(this); 
sqrt.addActionListener(this); 
reflect.addActionListener(this); 
postive.addActionListener(this); 
backspace.addActionListener(this); 
clear.addActionListener(this); 
 
setBounds(234,200,380,310); 
show(); 
}
public void actionPerformed(ActionEvent e) 
{ 
if(e.getActionCommand()=="1") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="2") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="3") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="4") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="5") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="6") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="7") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="8") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="9") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="0") 
{ 
if(oper2_begin==true) 
{ 
s_operator2+=e.getActionCommand(); 
display.setText(s_operator2); 
} 
else 
{ 
s_operator1+=e.getActionCommand(); 
display.setText(s_operator1); 
} 
} 
if(e.getActionCommand()=="+") 
{ 
s_operator1=display.getText(); 
display.setText(""); 
s_operator2=""; 
oper2_begin=true; 
pointed=false; 
pressoper='+'; 
} 
if(e.getActionCommand()=="-") 
{ 
s_operator1=display.getText(); 
display.setText(""); 
s_operator2=""; 
oper2_begin=true; 
pointed=false; 
pressoper='-'; 
} 
if(e.getActionCommand()=="x") 
{ 
s_operator1=display.getText(); 
s_operator2=""; 
display.setText(""); 
oper2_begin=true; 
pointed=false; 
pressoper='*'; 
} 
if(e.getActionCommand()=="/") 
{ 
s_operator1=display.getText(); 
s_operator2=""; 
display.setText(""); 
oper2_begin=true; 
pointed=false; 
pressoper='/'; 
} 
if(e.getActionCommand()=="sqrt") 
{ 
display.setText(String.valueOf(Math.sqrt(Float.parseFloat(display.getText())))); 
s_operator1=display.getText(); 
s_operator2=""; 
pressoper=' '; 
pointed=false; 
oper2_begin=true; 
} 
if(e.getActionCommand()=="1/x") 
{ 
if(Float.parseFloat(display.getText())!=0.0f) 
display.setText(String.valueOf(1.0/Float.parseFloat(display.getText()))); 
s_operator1=display.getText(); 
s_operator2=""; 
pressoper=' '; 
oper2_begin=true; 
} 
if(e.getActionCommand()=="abs") 
{ 
display.setText(String.valueOf(Math.abs(Float.parseFloat(display.getText())))); 
s_operator1=display.getText(); 
s_operator2=""; 
pressoper=' '; 
oper2_begin=true; 
} 
if(e.getActionCommand()=="+/-") 
{ s=display.getText(); 
s=String.valueOf(0.0-Float.parseFloat(s)); 
display.setText(s); 
if(oper2_begin==false) 
s_operator1=s; 
} 
if(e.getActionCommand()=="=") 
if(s_operator1!="" && s_operator2!="") 
{ 
switch(pressoper) 
{ 
case'+': 
display.setText(String.valueOf(Float.parseFloat(s_operator1)+Float.parseFloat(s_operator2))); 
break; 
case'-': 
display.setText(String.valueOf(Float.parseFloat(s_operator1)-Float.parseFloat(s_operator2))); 
break; 
case'*': 
display.setText(String.valueOf(Float.parseFloat(s_operator1)*Float.parseFloat(s_operator2))); 
break; 
case'/': 
display.setText(String.valueOf(Float.parseFloat(s_operator1)/Float.parseFloat(s_operator2))); 
break; 
} 
s_operator1=display.getText(); 
s_operator2=""; 
pressoper=' '; 
oper2_begin=true; 
} 
if(e.getActionCommand()=="." && pointed==false) 
{ 
if(oper2_begin==false) 
{ if(s_operator1=="") 
{ 
pointed=true; 
display.setText(s_operator1="0"+e.getActionCommand()); 
} 
else 
{ 
pointed=true; 
display.setText(s_operator1+=e.getActionCommand()); 
} 
} 
else 
{ 
if(s_operator2=="") 
{ 
pointed=true; 
display.setText(s_operator2="0"+e.getActionCommand()); 
} 
else 
{ 
pointed=true; 
display.setText(s_operator2+=e.getActionCommand()); 
} 
} 
} 
if(e.getActionCommand()=="backspace") 
{ 
s=display.getText(); 
s=s.substring(0,s.length()-1); 
display.setText(s); 
if(oper2_begin==false) 
s_operator1=s; 
} 
if(e.getActionCommand()=="clear") 
{ 
s_operator1=""; 
s_operator2=""; 
display.setText("0."); 
oper2_begin=false; 
pointed=false; 
} 
}
public void init()
{ 
new Constant(); 
}
}