myconmputer.java

java编的计算器小程序

import java.awt.*;
import java.awt.event.*;
public class MyConmputer implements ActionListener,WindowListener
{
	private Frame f;
	private TextField tf;
	private Button b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,b15,b16,b17,b18,b19,b20;
	private Panel p;
	private String str1="0";
	private String str2="0";
	private String str3="0";
	private String str5="0";
	private String str6="0";
	private float f1=0;
	private float f2=0;
	private float f3=0;
	private float f5=0;
	private float f6=0;
	private int count=0;
	private Math m;
	public MyConmputer()
	{
		f=new Frame("My Computer");
		tf=new TextField(30);
		p=new Panel();
		b1=new Button("X2");
		b2=new Button("√");
		b3=new Button("±");
		b4=new Button("C");
		b5=new Button("7");
		b6=new Button("8");
		b7=new Button("9");
		b8=new Button("+");
		b9=new Button("4");
		b10=new Button("5");
		b11=new Button("6");
		b12=new Button("-");
		b13=new Button("1");
		b14=new Button("2");
		b15=new Button("3");
		b16=new Button("*");
		b17=new Button("0");
		b18=new Button(".");
		b19=new Button("=");
		b20=new Button("/");
	}
	public void go()
	{
		f.add(tf,"North");
		p.setLayout(new GridLayout(5,4));
		p.add(b1);
		p.add(b2);
		p.add(b3);
		p.add(b4);
		p.add(b5);
		p.add(b6);
		p.add(b7);
		p.add(b8);
		p.add(b9);
		p.add(b10);
		p.add(b11);
		p.add(b12);
		p.add(b13);
		p.add(b14);
		p.add(b15);
		p.add(b16);
		p.add(b17);
		p.add(b18);
		p.add(b19);
		p.add(b20);
		b1.addActionListener(this);
		b2.addActionListener(this);
		b3.addActionListener(this);
		b4.addActionListener(this);
		b5.addActionListener(this);
		b6.addActionListener(this);
		b7.addActionListener(this);
		b8.addActionListener(this);
		b9.addActionListener(this);
		b10.addActionListener(this);
		b11.addActionListener(this);
		b12.addActionListener(this);
		b13.addActionListener(this);
		b14.addActionListener(this);
		b15.addActionListener(this);
		b16.addActionListener(this);
		b17.addActionListener(this);
		b18.addActionListener(this);
		b19.addActionListener(this);
		b20.addActionListener(this);
		
		f.addWindowListener(this);
		f.setSize(200, 200);
		f.add(p,"Center");
	    //f.pack();
		f.setVisible(true);
		tf.setText(str1);
		
	}
	public static void main(String args[])
	{
		MyConmputer c=new MyConmputer();
		c.go();
	}
	public void windowClosing(WindowEvent e)
	{
    	System.exit(0);
    }
    public void windowOpened(WindowEvent e){}
    public void windowIconified(WindowEvent e){}
    public void windowDeiconified(WindowEvent e){}
    public void windowClosed(WindowEvent e){}
    public void windowActivated(WindowEvent e){}
    public void windowDeactivated(WindowEvent e){}
	public void actionPerformed(ActionEvent e)
	{
		if((str1=="0"||str5!="0")&&e.getActionCommand()!="±")//||str5!="0"
		  {str1=e.getActionCommand();
		   tf.setText(str1);
		   str5="0";
          }
		else if(e.getActionCommand()!="+"&&e.getActionCommand()!="-"&&e.getActionCommand()!="*"&&e.getActionCommand()!="/"&&e.getActionCommand()!="="&&e.getActionCommand()!="±"&&e.getActionCommand()!="X2"&&e.getActionCommand()!="√")
		{
			
			str1=str1+e.getActionCommand();
			tf.setText(str1);
			str2=str2+e.getActionCommand();
			//String str=e.getActionCommand();
		
    	}
    	 else if(e.getActionCommand()=="+"||e.getActionCommand()=="-"||e.getActionCommand()=="*"||e.getActionCommand()=="/")
		  {
		  	f1=Float.valueOf(str1).floatValue();
		  	str1=str1+e.getActionCommand();
		  	str2="0";
		  	str3=e.getActionCommand();
		  	tf.setText(str1);
		  	System.out.print("f1="+f1);
		  }
		  else if(e.getActionCommand()=="=")
		  {
		  	f2=Float.valueOf(str2).floatValue();
		  	System.out.print("f2="+f2);
		  	if(str3=="+")
		    {f3=f1+f2;
		  	    str5=Float.toString(f3);
		    	System.out.print("f3="+f3);
		  	    tf.setText(str5);		  
		    }
		    if(str3=="-")
		    {f3=f1-f2;
		    str5=Float.toString(f3);
		  	System.out.print("f3="+f3);
		  	tf.setText(str5);
		    }
		    if(str3=="*")
		    {f3=f1*f2;
		    str5=Float.toString(f3);
		  	System.out.print("f3="+f3);
		  	tf.setText(str5);
		    }
		    if(str3=="/")
		    {f3=f1/f2;
		    str5=Float.toString(f3);
		  	System.out.print("f3="+f3);
		  	tf.setText(str5);
		    }
		  }
	     if(e.getSource()==b3)
	      { 
	         if(str5!="0")
	         { f6=Float.valueOf(str5).floatValue();
	           f6=f6*(-1);
	           str5=Float.toString(f6);
	           tf.setText(str5);
	          // tf.setText(str5);
	           System.out.print("str1="+str1+"str5="+str5);
	         }
	         else {
	         	f1=Float.valueOf(str1).floatValue();
	         f1=f1*(-1);
	         str1=Float.toString(f1);
	         tf.setText(str1);
	       }

         	System.out.print("count="+count);
         }
	     if(e.getSource()==b4)
		{ str1="0";
		  str2="0";
		  str3="0";
		  //str5="0";
		  f1=0;
		  f2=0;
		  f3=0;
		  System.out.print("f1="+f1);
		  tf.setText(str1);
	    }
	     if(e.getSource()==b1)
	     {
	     	str1="3.1415926535";
		tf.setText(str1);
	    }
	}	
}