Java计算器程序-优快云博客

这几天的主要学习内容是数据类型的转换和各种方法的使用，写了一个计算器的小程序，虽然l逻辑控制上还有很多问题，但还是发出来，请过路高手指点：

运行效果：

源代码：

import java.awt.BorderLayout; import java.awt.Color; import java.awt.Container; import java.awt.Font; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.text.DecimalFormat; import javax.swing.BorderFactory; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; public class jsq extends JFrame implements ActionListener { JLabel jlmain,jlop1,jlop2,jlfh1,jlfh2; JButton myb[]; String strkey[]={"M+", "M-", "C", "←", "×", "Sqrt", "7", "8","9", "÷", "㎡", "4", "5", "6", "+", "1/x", "1", "2", "3", "-","+/-","0","00",".","="}; String strkey1[]={"累加", "累减", "清除", "退格", "乘以", "开2次方", "数字7", "数字8","数字9", "除以", "平方", "数字4", "数字5", "数字6", "加上", "倒数", "数字1", "数字2", "数字3", "减去","正负互换","数字0","数字00","小数点","等于"}; JPanel p1; public jsq() { super("计算器"); setSize(468, 375); setResizable(false); setLocationRelativeTo(null); setLayout(new BorderLayout()); setResizable(false); setDefaultCloseOperation(DISPOSE_ON_CLOSE); Container ct=getContentPane(); Font f1=new Font("黑体",1,60);//显示屏数字字体 Font f2=new Font("宋体",1,14);//显示屏小字体 Font f3=new Font("黑体",1,20);//按钮字体 Color mycolor=new Color(26, 29, 34); ct.setLayout(null); ct.setBackground(Color.GRAY); myb=new JButton[25]; jlmain=new JLabel("0"); jlmain.setFont(f1); jlop1=new JLabel("0"); jlop1.setFont(f2); jlop2=new JLabel("0"); jlop2.setFont(f2); jlfh1=new JLabel(""); jlfh1.setFont(f2); jlfh2=new JLabel(""); jlfh2.setFont(f2); p1=new JPanel(); p1.setLayout(null); p1.setBackground(mycolor); jlmain.setBounds(15, 20, 410, 55); jlmain.setBackground(new Color(122,134,122)); jlmain.setOpaque(true); jlmain.setForeground(Color.GREEN); jlmain.setFont(f1); jlmain.setHorizontalAlignment(JLabel.RIGHT); jlmain.setBorder (BorderFactory.createLoweredBevelBorder()); jlop1.setHorizontalAlignment(JLabel.LEFT); jlop2.setHorizontalAlignment(JLabel.LEFT); jlfh1.setHorizontalAlignment(JLabel.CENTER); jlfh2.setHorizontalAlignment(JLabel.CENTER); jlop1.setForeground(Color.GREEN); jlop2.setForeground(Color.GREEN); jlfh1.setForeground(Color.GREEN); jlfh2.setForeground(Color.GREEN); jlop1.setFont(f2); jlfh1.setFont(f2); jlfh2.setFont(f2); jlop1.setBounds(75, 3, 140, 14); jlop2.setBounds(221, 3, 140, 14); jlfh1.setBounds(366, 3, 30, 14); jlfh2.setBounds(400, 3, 35, 14); ct.add(p1); p1.setBounds(10, 5, 440, 80); p1.add(jlmain); p1.add(jlop1); p1.add(jlop2); p1.add(jlfh1); p1.add(jlfh2); p1.setBorder (BorderFactory.createLoweredBevelBorder()); for(int i=0;i<strkey.length;i++) { int h=(int) Math.ceil(i/5); myb[i]=new JButton(); myb[i].setText(strkey[i]); myb[i].setFont(f3); myb[i].setBounds((i*90+10)-h*450,(h+1)*50+40,80,40); myb[i].setToolTipText(strkey1[i]); myb[i].addActionListener(this); myb[i].setActionCommand(String.valueOf(i)); //设置按钮的command属性，以便下边调用 myb[i].setFocusPainted(false); //去掉焦点框 if(!myb[i].getToolTipText().substring(0, 2).equals("数字")) { myb[i].setForeground(Color.RED); } ct.add(myb[i]); } setVisible(true); } public static void main(String[] args) { jsq hh= new jsq(); hh.setVisible(true); } public void actionPerformed(ActionEvent e) { boolean isd=jlmain.getText().endsWith(".")?true:false;//判断最后一位是否为小数点 boolean youd=jlmain.getText().indexOf(".")>0?true:false;//判断是否有小数点 int ookk=Integer.valueOf(e.getActionCommand()); DecimalFormat df = new DecimalFormat();//定义格式化器 //String style = "0.0000";//定义要显示的数字的格式，保留四位小数 String style = "0.####";//定义要显示的数字的格式，保留四位小数但不显示多余的零 df.applyPattern(style);// 将格式应用于格式化器 switch (ookk) { case 0: jlfh1.setText("M+"); //如果最后一位为小数点就去掉 if (isd){jlmain.setText(jlmain.getText().substring(0,jlmain.getText().length()-1));} jlop1.setText(String.valueOf(df.format(Double.valueOf(jlmain.getText())+Double.valueOf(jlop1.getText())))); jlmain.setText("0"); break; case 1: jlfh1.setText("M-"); //如果最后一位为小数点就去掉 if (isd){jlmain.setText(jlmain.getText().substring(0,jlmain.getText().length()-1));} jlop1.setText(String.valueOf(df.format(Double.valueOf(jlop1.getText())-Double.valueOf(jlmain.getText())))); jlmain.setText("0"); break; case 2://clear jlmain.setText("0"); jlop1.setText("0"); jlop2.setText("0"); jlfh1.setText(""); jlfh2.setText(""); break; case 3://退格 jlmain.setText(jlmain.getText().length()>=1?jlmain.getText().substring(0, jlmain.getText().length()-1):"0"); if(jlmain.getText().length()<1) {jlmain.setText("0");} break; case 4://乘以 jlfh2.setText("×"); jlop2.setText(isd?jlmain.getText().substring(0, jlmain.getText().length()-1):jlmain.getText()); jlmain.setText("0"); break; case 5: //jlfh2.setText("Sqrt");单目运算，直接得出结果 if(isd) {jlmain.setText(jlmain.getText().substring(0, jlmain.getText().length()-1));} if (Double.valueOf(jlmain.getText())>=0) {jlmain.setText(String.valueOf(df.format(Math.sqrt(Double.valueOf(jlmain.getText())))));} if(Double.valueOf(jlmain.getText())==0) {jlmain.setText("0");} break; case 9://除以 if (Double.valueOf(jlmain.getText())!=0) { jlfh2.setText("÷"); jlop2.setText(isd?jlmain.getText().substring(0, jlmain.getText().length()-1):jlmain.getText()); jlmain.setText("0"); } break; case 10: //jlfh2.setText("㎡");单目运算，直接得出结果 if(isd) {jlmain.setText(jlmain.getText().substring(0, jlmain.getText().length()-1));} if(Double.valueOf(jlmain.getText())*Double.valueOf(jlmain.getText())>Double.MAX_VALUE||Double.valueOf(jlmain.getText())*Double.valueOf(jlmain.getText())<Double.MIN_VALUE) {jlmain.setText("0");} jlmain.setText(String.valueOf(df.format(Double.valueOf(jlmain.getText())*Double.valueOf(jlmain.getText())))); if(Double.valueOf(jlmain.getText())==0) {jlmain.setText("0");} break; case 14: jlfh2.setText("+"); jlop2.setText(isd?jlmain.getText().substring(0, jlmain.getText().length()-1):jlmain.getText()); jlmain.setText("0"); break; case 15: //jlfh2.setText("1/x");单目运算，直接得出结果 if(isd) {jlmain.setText(jlmain.getText().substring(0, jlmain.getText().length()-1));} if (Double.valueOf(jlmain.getText())!=0){jlmain.setText(String.valueOf(df.format(1/Double.valueOf(jlmain.getText()))));} if(Double.valueOf(jlmain.getText())==0) {jlmain.setText("0");} break; case 19: jlfh2.setText("-"); jlop2.setText(isd?jlmain.getText().substring(0, jlmain.getText().length()-1):jlmain.getText()); jlmain.setText("0"); break; case 20: //jlfh2.setText("+/-");单目运算，直接得出结果 if((Double.valueOf(jlmain.getText())!=0||youd)&&jlmain.getText().length()>0) { jlmain.setText(jlmain.getText().substring(0, 1).equals("-")?jlmain.getText().substring(1):"-"+jlmain.getText()); } break; case 22://00 if(!youd||(youd && jlmain.getText().indexOf(".")>jlmain.getText().length()-3)) { if(jlmain.getText().length()<16&&!jlmain.getText().equals("0")) {jlmain.setText(jlmain.getText()+"00");} } break; case 23://小数点 if(!youd) {jlmain.setText(jlmain.getText()+".");} break; case 24://等于 if(isd) {jlmain.setText(jlmain.getText().substring(0, jlmain.getText().length()-1));} if(jlfh2.getText().equals("+")) {jlmain.setText(String.valueOf(df.format(Double.valueOf(jlop2.getText())+Double.valueOf(jlmain.getText()))));} if(jlfh2.getText().equals("-")) {jlmain.setText(String.valueOf(df.format(Double.valueOf(jlop2.getText())-Double.valueOf(jlmain.getText()))));} if(jlfh2.getText().equals("×")) {jlmain.setText(String.valueOf(df.format(Double.valueOf(jlop2.getText())*Double.valueOf(jlmain.getText()))));} if(jlfh2.getText().equals("÷")&& Double.valueOf(jlmain.getText())!=0) {jlmain.setText(String.valueOf(df.format(Double.valueOf(jlop2.getText())/Double.valueOf(jlmain.getText()))));} if(jlfh2.getText().length()!=1&&jlfh1.getText().equals("M+")&&(jlfh2.getText().equals("÷")||Double.valueOf(jlmain.getText())!=0)) {jlmain.setText(String.valueOf(df.format(Double.valueOf(jlop1.getText())+Double.valueOf(jlmain.getText())))); } if(jlfh2.getText().length()!=1&&jlfh1.getText().equals("M-")&&(jlfh2.getText().equals("÷")||Double.valueOf(jlmain.getText())!=0)) {jlmain.setText(String.valueOf(df.format(Double.valueOf(jlop1.getText())-Double.valueOf(jlmain.getText()))));} jlmain.setText(String.valueOf(Double.parseDouble(jlmain.getText()))); if(jlmain.getText().equals("0.0")) {jlmain.setText("0");} break; default: if(jlmain.getText().length()<12) { if(!youd||(youd && jlmain.getText().indexOf(".")!=jlmain.getText().length()-5)) { if(jlmain.getText().substring(0, 1).equals("0")&&!youd) {jlmain.setText(strkey1[Integer.valueOf(e.getActionCommand())].trim().substring(2, 3));} else{jlmain.setText(jlmain.getText()+strkey1[Integer.valueOf(e.getActionCommand())].trim().substring(2, 3));} } } break; } } }

JAVA学习第十五天