文本文件錯誤掃描

Question

我在寫代碼刪除一個字的文本文件，當用戶輸入，但我不能似乎得到掃描器部工作

public static void Option2Method() throws IOException 
{ 

File inputFile = new File("wordlist.txt"); 
File tempFile = new File("TempWordlist.txt"); 
String lineToRemove = JOptionPane.showInputDialog(null, "Enter a word to remove"); 
Scanner reader = new Scanner(inputFile); 
Scanner writer =new Scanner(tempFile); 
String currentLine; 

while((currentLine = reader.nextLine()) != null) 
{ 
String trimmedLine = currentLine.trim(); 
if(trimmedLine.equals(lineToRemove)) continue; 
writer.print(currentLine + "\n"); 
} 
reader.close(); 
writer.close(); 
inputFile.delete(); 
tempFile.renameTo(inputFile); 
} 

Answer 1

Scanner並不意味着寫入文件，因此沒有一個write()方法。您可以改用BufferedWriter。

例子：

public static void Option2Method() throws IOException { 

    File inputFile = new File("wordlist.txt"); 
    FileWriter fstream = new FileWriter("TempWordlist.txt", true); 
    BufferedWriter writer = new BufferedWriter(fstream); 

    File tempFile = new File("TempWordlist.txt"); 
    String lineToRemove = JOptionPane.showInputDialog(null, "Enter a word to remove"); 
    Scanner reader = new Scanner(inputFile); 

    while (reader.hasNextLine()) { 
     String trimmedLine = reader.nextLine().trim(); 
     if (trimmedLine.equals(lineToRemove)) 
      continue; 

     writer.write(trimmedLine + "\n"); 
    } 

    reader.close(); 
    writer.close(); 
    inputFile.delete(); 
    tempFile.renameTo(inputFile); 
} 

使用PrintWriter：

File inputFile = new File("wordlist.txt"); 
    PrintWriter writer = new PrintWriter(new BufferedWriter(new FileWriter("TempWordlist.txt", true))); 

    File tempFile = new File("TempWordlist.txt"); 
    String lineToRemove = JOptionPane.showInputDialog(null, "Enter a word to remove"); 
    Scanner reader = new Scanner(inputFile); 

    while (reader.hasNextLine()) { 
     String trimmedLine = reader.nextLine().trim(); 
     if (trimmedLine.equals(lineToRemove)) 
      continue; 

     writer.print(trimmedLine + "\n"); 
    } 

    reader.close(); 
    writer.close(); 
    inputFile.delete(); 
    tempFile.renameTo(inputFile); 

Answer 2

Scanner沒有print方法。它用於掃描一個文件和讀取來自它的數據。

如果你想寫入一個文件，使用this或that或只是谷歌「java write to file」