java如何将JOptionPane中的文本存储到文本文件中

Question

我是个新手。我试图从JOptionPane中获取用户输入的文本，并将其存储到文本文件中。此后，我想阅读课文，并用它做什么

能帮我保存输入的文本吗？谢谢 这是我的代码：

import javax.swing.JOptionPane;
import java.io.*;

public class RunProgram {


public static void introView() {
    //The introduction
    JOptionPane.showMessageDialog(null, "Welcome." +
            " To begin, please click the below button to input some information " +
            "about yourself.");
}

public static void personInput() {

    try{
        File userInfo = new File("C:\\Users\\WG Chasi\\workspace\\" +
                "Useful Java\\products\\UserInfo.txt");
        userInfo.getParentFile().mkdirs();
        FileWriter input = new FileWriter(userInfo);

        JOptionPane userInput = new JOptionPane();
        userInput.showInputDialog("Enter details");/*I want to store the text from the InputDialog into the text file*/
        //Write text from the JOptionPane into UserInfo.txt
    }catch(Exception e){
        JOptionPane.showMessageDialog(null, "An ERROR has occured.");
    }
}


public static void main(String[] args) {
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            introView();
            personInput();
        }
    });
}

}

Answer 1

试试这个

     public static void personInput() 
     {

        String whatTheUserEntered = JOptionPane.showInputDialog("Enter details");

        JFileChooser chooser = new JFileChooser();
        chooser.setCurrentDirectory( new File( "./") );
        int actionDialog = chooser.showSaveDialog(yourWindowName); //where the dialog should render
        if (actionDialog == JFileChooser.APPROVE_OPTION)
        {
            File fileName = new File(chooser.getSelectedFile( ) + ".txt" ); //opens a filechooser dialog allowing you to choose where to store the file and appends the .txt mime type
            if(fileName == null)
                return;
            if(fileName.exists()) //if filename already exists
            {
                actionDialog = JOptionPane.showConfirmDialog(yourWindowName,
                                   "Replace existing file?");
                if (actionDialog == JOptionPane.NO_OPTION) //open a new dialog to confirm the replacement file
                    return;
            }
            try
            {
                BufferedWriter out = new BufferedWriter(new FileWriter(fileName)); 

                    out.write(whatTheUserEntered );
                    out.close(); //write the data to the file and close, please refer to what madProgrammer has explained in the comments here about where the file may not close correctly. 
            }
            catch(Exception ex)
            {
                 System.err.println("Error: " + ex.getMessage());
            }
        }
      }

我基本上是试图从输入对话框中获取文本，并将其写入您选择的文件中。该文件将使用附加字符串“.txt”作为文本文件写入，该字符串将mime类型设置为文本

告诉我进展如何

Answer 2

根据你的需要，你有很多潜在的选择

你可以

将内容写入Properties文件

private Properties properties = new Properties();

//...
String name = JOptionPane.showInputDialog("What is your name?");
properties.set("user.name", name);

//...
protected void savePropeties() throws IOException {
    try (OutputStream os = new FileOutputStream(new File("User.properties"))) {
        properties.store(os, "User details");
    }
}

protected void loadPropeties() throws IOException {
    try (InputStream is = new FileInputStream(new File("User.properties"))) {
        // Note, this will overwrite any previously existing
        // values...
        properties.load(is);
    }
}

正如您所见，您必须亲自加载并保存内容。这意味着，你可以控制文件的位置

你可以

利用PreferencesAPI

String name = JOptionPane.showInputDialog("What is your name?");
Preferences preferences = Preferences.userNodeForPackage(RunProgram.class);
preferences.put("user.name", name);

然后你可以简单地使用像

Preferences preferences = Preferences.userNodeForPackage(RunProgram.class);
String name = preferences.get("user.name", null);

检索值

这样做的好处是，存储过程会照顾到您，但您会失去对数据存储位置的控制

你可以

• 以自己的格式将数据写入文件。这需要大量的工作和开销，但您不仅可以控制文件的位置，还可以控制维护数据的格式。有关更多详细信息，请参见Basic I/O
• 以XML格式编写数据，这提供了一定级别的分层控制（如果这很重要的话），但确实增加了管理的复杂性