我想知道如何计算计算器程序中的空间。现在它被设置为只有在每个值后面都有一个空格时才起作用。如果还有多个空间,我希望它能够工作。我尝试做一些事情(在我执行的操作中,在 '=' 符号测试下),但它并没有真正起作用。所以想知道如何让它考虑多个空格(比如如果在下一个值之前有多个空格,那么它应该认识到是这种情况,并删除额外的空格)。谢谢
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
public class GUI extends JFrame implements ActionListener
{
JPanel buttonPanel, topPanel, operationPanel;
JTextField display = new JTextField(20);
doMath math = new doMath();
String s = "";
String b= "";
//int counter;
JButton Num1;
JButton Num2;
JButton Num3;
JButton Num4;
JButton Num5;
JButton Num6;
JButton Num7;
JButton Num8;
JButton Num9;
JButton Num0;
JButton Add;
JButton Sub;
JButton Mult;
JButton Div;
JButton Eq;
JButton Clr;
JButton Space;
public GUI()
{
super("Calculator");
setSize(400,400);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel mainPanel = new JPanel();
mainPanel.setLayout(new GridLayout (2,1));
buttonPanel = new JPanel();
buttonPanel.setLayout(new GridLayout(5, 4));
buttonPanel.add(Num1 = new JButton("1"));
buttonPanel.add(Num2 = new JButton("2"));
buttonPanel.add(Num3 = new JButton("3"));
buttonPanel.add(Num4 = new JButton("4"));
buttonPanel.add(Num5 = new JButton("5"));
buttonPanel.add(Num6 = new JButton("6"));
buttonPanel.add(Num7 = new JButton("7"));
buttonPanel.add(Num8 = new JButton("8"));
buttonPanel.add(Num9 = new JButton("9"));
buttonPanel.add(Num0 = new JButton("0"));
buttonPanel.add(Clr = new JButton("C"));
buttonPanel.add(Eq = new JButton("="));
buttonPanel.add(Add = new JButton("+"));
buttonPanel.add(Sub = new JButton("-"));
buttonPanel.add(Mult = new JButton("*"));
buttonPanel.add(Div = new JButton("/"));
buttonPanel.add(Space = new JButton("Space"));
Num1.addActionListener(this);
Num2.addActionListener(this);
Num3.addActionListener(this);
Num4.addActionListener(this);
Num5.addActionListener(this);
Num6.addActionListener(this);
Num7.addActionListener(this);
Num8.addActionListener(this);
Num9.addActionListener(this);
Num0.addActionListener(this);
Clr.addActionListener(this);
Eq.addActionListener(this);
Add.addActionListener(this);
Sub.addActionListener(this);
Mult.addActionListener(this);
Div.addActionListener(this);
Space.addActionListener(this);
topPanel = new JPanel();
topPanel.setLayout(new FlowLayout());
topPanel.add(display);
add(mainPanel);
mainPanel.add(topPanel, BorderLayout.NORTH);
mainPanel.add(buttonPanel, BorderLayout.SOUTH);
setVisible(true);
}
public void actionPerformed(ActionEvent e)
{
JButton source = (JButton)e.getSource();
String text = source.getText();
int counter = 0;
if (text.equals("="))
{
doMath math = new doMath();
for(int i = 0; i <b.length(); i++)
{
String c = b.substring(i,(i+1));
String d = b.substring((i+1),(i+2));
String temp = "";
if( c.equals(" ") && c.equals(d))
{
temp = b.substring(0,i)+(b.substring(i+1));
b = temp;
}
}
int result = math.doMath1(b);
String answer = ""+result;
display.setText(answer);
}
else if(text.equals("Space"))
{
counter ++;
if(counter <2)
{
b+= " ";
display.setText(b);
}
else
{
b+="";
display.setText(b);
}
}
else if (text.equals("C"))
{
b = "";
display.setText(b);
}
else
{
b += (text);
display.setText(b);
}
counter = 0;
}
}