Java实现简单的计算器

旧城等待， 2023-02-14 06:59 36阅读 0赞

先来看看界面效果

![20200601170105991.png][]

源码如下：

package test1;
    
    import java.awt.Frame;
    import java.awt.TextField;
    import java.awt.Button;
    import java.awt.Panel;
    import java.awt.GridLayout;
    
    import java.awt.event.WindowAdapter;
    import java.awt.event.WindowEvent;
    
    import java.awt.event.ActionEvent;
    import java.awt.event.ActionListener;
    public class calculate {
    	TextField tfResult;
    	Button btNum[],btOper[],btPoint,btEqual,btBack,btSqrt,btPingfang,btLifang;
    	int num1,num2;//操作数
    	char oper;//操作符
    	boolean isNum;//代表数字标志位
    	public void init(){
    		Frame f;
    		
    		tfResult=new TextField();
    		
    		btNum=new Button[10];//数组对象
    		for(int i=0;i<=9;i++){
    			btNum[i]=new Button(i+"");
    		}
    		btOper=new Button[4];
    		btOper[0]=new Button("+");
    		btOper[1]=new Button("-");
    		btOper[2]=new Button("*");
    		btOper[3]=new Button("/");
    		
    		btPoint=new Button(".");
    		btEqual=new Button("=");
    		btBack=new Button("Backspace");
    		btSqrt=new Button("Sqrt");
    		btPingfang=new Button("2");
    		btLifang=new Button("3");
    		f=new Frame("小羊羔的计算器！");
    		
    		f.setSize(300,300);
    		
    		//放置组件
    		f.add(tfResult,"North");
    		Panel panel=new Panel();
    		f.add(panel,"Center");
    		GridLayout gl=new GridLayout(5,4);
    		panel.setLayout(gl);
    		panel.add(btNum[1]);
    		panel.add(btNum[2]);
    		panel.add(btNum[3]);
    		panel.add(btOper[0]);
    		
    		panel.add(btNum[4]);
    		panel.add(btNum[5]);
    		panel.add(btNum[6]);
    		panel.add(btOper[1]);
    		
    		panel.add(btNum[7]);
    		panel.add(btNum[8]);
    		panel.add(btNum[9]);
    		panel.add(btOper[2]);
    		
    		panel.add(btNum[0]);
    		panel.add(btPoint);
    		panel.add(btEqual);
    		panel.add(btOper[3]);
    		
    		panel.add(btBack);
    		panel.add(btSqrt);
    		panel.add(btPingfang);
    		panel.add(btLifang);
    		f.setVisible(true);
    		
    		//注册监听
    		f.addWindowListener(new MyWinLis());
    		//数字按钮注册监听
    		MyNumLis mnl=new MyNumLis();
    		for(int i=0;i<=9;i++)
    			btNum[i].addActionListener(mnl);
    		
    		//操作符按钮注册监听
    		MyOperLis mol=new MyOperLis();
    		for(int j=0;j<=3;j++)
    			btOper[j].addActionListener(mol);
    		//等号按钮注册监听
    		MyEqualLis mel=new MyEqualLis();
    		btEqual.addActionListener(mel);
    		//删除按钮注册监听
    		MyBackLis mbl=new MyBackLis();
    		btBack.addActionListener(mbl);
    		//开根号按钮注册监听
    		MySqrtLis msl=new MySqrtLis();
    		btSqrt.addActionListener(msl);
    		//平方按钮注册监听
    		MyPingfangLis mpl=new MyPingfangLis();
    		btPingfang.addActionListener(mpl);
    		//百分号注册监听
    		MyLifangLis mll=new MyLifangLis();
    		btLifang.addActionListener(mll);
    	}
    	//定义监听器类
    	class MyNumLis implements ActionListener{
    		public void actionPerformed(ActionEvent e){
    			String t=e.getActionCommand();
    			String s=tfResult.getText();
    			if(isNum==false)
    				tfResult.setText(t);
    			else 
    				tfResult.setText(s+t);
    			isNum=true;
    		}
    	}
    	class MySqrtLis implements ActionListener{
    		public void actionPerformed(ActionEvent e){
    			double t=Double.parseDouble(tfResult.getText());
    			tfResult.setText(Math.sqrt(t)+"");
    			isNum=false;
    		}
    	}
    	class MyPingfangLis implements ActionListener{
    		public void actionPerformed(ActionEvent e){
    			num1=Integer.parseInt(tfResult.getText());
    			tfResult.setText(num1*num1+"");
    		}
    	}
    	class MyLifangLis implements ActionListener{
    		public void actionPerformed(ActionEvent e){
    			num1=Integer.parseInt(tfResult.getText());
    			tfResult.setText(num1*num1*num1+"");
    		}
    	}
    	class MyOperLis implements ActionListener{
    		public void actionPerformed(ActionEvent e){
    			num1=Integer.parseInt(tfResult.getText());//转化为INT
    			oper=e.getActionCommand().charAt(0);
    			isNum=false;
    		}
    	}
    	class MyEqualLis implements ActionListener{
    		public void actionPerformed(ActionEvent e){
    			int result=0;
    			isNum=false;
    			num2=Integer.parseInt(tfResult.getText());
    			switch(oper){
    				case '+':result=num1+num2;break;
    				case '-':result=num1-num2;break;
    				case '*':result=num1*num2;break;
    				case '/':result=num1/num2;break;
    			}
    			tfResult.setText(result+"");
    		}
    	}
    	class MyBackLis implements ActionListener{
    		public void actionPerformed(ActionEvent e){
    			tfResult.setText("");
    			isNum=false;
    		}
    	}
    	class MyWinLis extends WindowAdapter{
    		public void windowClosing(WindowEvent e){
    			e.getWindow().setVisible(false);
    			e.getWindow().dispose();
    			System.exit(0);
    		}
    	}
    	
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    		new calculate().init();
    	}
    
    }

11×5=？界面如下：

![20200601170146824.png][]

![20200601170211411.png][]

![2020060117022053.png][]

[20200601170105991.png]: https://img-blog.csdnimg.cn/20200601170105991.png
[20200601170146824.png]: https://img-blog.csdnimg.cn/20200601170146824.png
[20200601170211411.png]: https://img-blog.csdnimg.cn/20200601170211411.png
[2020060117022053.png]: https://img-blog.csdnimg.cn/2020060117022053.png