尝试将 JTextField 转换为 Integer 时出现 NumberFormatException

Question

我已经尝试了很多方法，但似乎仍然无法修复此错误，所以我要问自己的问题。

我一直认为错误出在我尝试将 JTextfield 转换为 int 的 ActionEvent 上，但它可能是其他原因？谢谢:)

我在另一个 class 中有一个对象，我需要将数据发送到该对象以构建它。这是对象

/**
 * Constructor
 */
public Account(int startAmount, int balance, int credit, String Name, String    Address)  {       
    openingBalance = startAmount;
    currentBalance = balance;
    creditLimit = credit;
    accountName = Name;
    accountAddress = Address;

    numOfAccounts++;
}

现在我的其余代码，

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.*;
import javax.swing.*;

public class AccountGUI extends JFrame{


private static final long serialVersionUID = 1L;

String Name;
String Address;
int balance;
int credit;
GridBagConstraints gbc = new GridBagConstraints();

public AccountGUI(){

    setLayout(new GridBagLayout());

    gbc.fill = GridBagConstraints.HORIZONTAL;
    gbc.ipadx = 20;
    gbc.ipady = 20;

    JLabel enterYourName = new JLabel("Name:");
    JTextField textBoxToEnterName = new JTextField(20);
    JPanel firstPanel = new JPanel();
    addHelper(enterYourName,0,0);
    addHelper(textBoxToEnterName,1,0);

    JLabel enterYourAddress = new JLabel("Address:");
    JTextField textBoxToEnterAddress = new JTextField(20);
    addHelper(enterYourAddress,0,1);
    addHelper(textBoxToEnterAddress,1,1);

    JLabel enterYourBalance = new JLabel("Current Balance:");
    JTextField textBoxToEnterBalance = new JTextField(0);
    addHelper(enterYourBalance, 0,2);
    addHelper(textBoxToEnterBalance, 1,2);

    JLabel enterYourCreditLimit = new JLabel("Credit Limit:");
    JTextField textBoxToEnterCreditLimit = new JTextField(20);
    addHelper(enterYourCreditLimit, 0, 3);
    addHelper(textBoxToEnterCreditLimit, 1,3);

    JButton submit = new JButton("Submit");
    submit.addActionListener(new ActionListener()
    {
        @Override
        public void actionPerformed(ActionEvent e)
        {
            Name = enterYourName.getText();
            Address = enterYourAddress.getText();
            try {
                int balance = Integer.parseInt(enterYourBalance.getText().trim());
            }
            catch(NumberFormatException ex)
            {
                System.out.println("Exception : "+ex);
            }
            try {
                int credit = Integer.parseInt(enterYourCreditLimit.getText().trim());
            }
            catch(NumberFormatException ex)
            {
                System.out.println("Exception : "+ex);
            }
            Account record = new Account(0, balance, credit, Name, Address);
        }
    });
    addHelper(submit,0,4);

    setTitle("AccountGUI");
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    pack();
    setLocationRelativeTo(null);


}

private void addHelper(JComponent item, int x, int y){
    gbc.gridx= x;
    gbc.gridy= y;
    add(item,gbc);
}

public static void main(String[] args) {
    AccountGUI promptForName = new AccountGUI();
    promptForName.setVisible(true); 
}


}

我收到的错误信息是

Exception : java.lang.NumberFormatException: For input string: "Current Balance:" 
Exception : java.lang.NumberFormatException: For input string: "Credit Limit:"

Answer 1

您要求从 enterYourBalance 解析，但您的 JTextField 是 textBoxToEnterBalance。在您的代码中将相应的行替换为：

int balance = Integer.parseInt(textBoxToEnterBalance.getText().trim());

Answer 2

int balance = Integer.parseInt(enterYourBalance.getText().trim());

enterYourBalance 是 JLabel 对象

这样编辑

    int balance = Integer.parseInt(textBoxToEnterBalance .getText().trim());

尝试从 JTextField 而不是从 JLabel 获取值

Answer 3

JLabel enterYourBalance = new JLabel("Current Balance:");
JTextField textBoxToEnterBalance = new JTextField(0);
...
int balance = Integer.parseInt(enterYourBalance.getText().trim());`

enterYourBalance.getText().trim() 将 return "Current Balance:" 解析为 int 失败。改成 textBoxToEnterBalance.getText().trim() 从文本字段中获取文本。

尝试将 JTextField 转换为 Integer 时出现 NumberFormatException

NumberFormatException when trying to convert JTextField to Integer

java

user-interface

constructor

object

jtextfield