Java讀取文本文件並將每一行另存為新的字符串數組

Question

我正在嘗試構建一個將讀取文本文件的應用程序，然后將每一行文本存儲為一個數組列表。

這是我的文本文件：

1 , Where is the white house? , Paris , Amsterdam , New York , Washington 
2 , The Sopranos Is a..? , Italian Food , Tv series , Kind of Knife , A Book
3 , The Capital City Of Brazil is? , Rio de Janeiro, Amsterdam , Brazilia , Washington
4 ,Who Invanted The Phone ?, Alexander Graham Bell, Albert Einstein , Pinokio , Snoop Doog 

我基本上是在嘗試構建一個Trivia應用程序，該應用程序將從文本文件中選擇每一行，然后將所選行拆分為字符串數組，最后在屏幕上打印一個問題和四個答案。

到目前為止，這是我的代碼：

public class QuestionSql extends Activity {

    private String[] value;
    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.highscore);
        readFile();

    }


    private void readFile() {
        // TODO Auto-generated method stub
        AssetManager manger;
        String line = null;

        try {
            manger = getAssets();
            InputStream is = manger.open("text.txt");
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);
            while ((line = br.readLine()) != null) {
                value = line.split(",");


                //System.out.print(value);
            }
            br.close();


        } catch (IOException e1) {
            System.out.println("not good");

        }

    }

}

問題是該應用程序僅打印文本文件的最后一行

---

謝謝您的回答，對我有很大幫助！ 到目前為止，這是我的代碼：

公共類QuestionSql擴展Activity {

private String[] value;
private List<String[]> collection;

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.highscore);

    readFile();
    convertListToString()
}


  private void convertListToString() {


    value = collection.toArray(new String[collection.size()]);

  }







private void readFile() {
    // TODO Auto-generated method stub
    AssetManager manger;
    String line = null;
    collection = new ArrayList<String[]>();

    try {
        manger = getAssets();
        InputStream is = manger.open("text.txt");
        InputStreamReader isr = new InputStreamReader(is);
        BufferedReader br = new BufferedReader(isr);
        while ((line = br.readLine()) != null) {
            value = line.split(",");
           collection.add(value);

        }
        br.close();


    } catch (IOException e1) {
        System.out.println("not good");

    }

}

}

現在，我需要轉換：collection = new ArrayList（）; 轉換為string []，這樣我就可以在應用程序按鈕上設置文本了。 有任何想法嗎？

Answer 1

如果要將每一行存儲到字符串數組中，則需要創建“字符串數組的結構”

因此，最有效的選擇是創建將保存字符串數組的List<String[]> 。

您的方法不起作用的原因是，您為每行分配了新值到相同的字符串數組（始終被重寫），並且在循環之后，字符串數組包含最后一行的值。

List<String[]> collection = new ArrayList<String[]>();
String[] temp;
while ((line = br.readLine()) != null) {
   temp = line.split(",");
   if (temp.length > 0) {
      collection.add(temp);
   }
}

但是，如果要創建僅包含值的List（我有點困惑），可以使用：

List<String> collection = new ArrayList<String>();
String[] temp;
while ((line = br.readLine()) != null) {
   temp = line.split(",");
   if (temp.length > 0) {
      for (String s: temp) {
         collection.add(s);
      }
   }
}

Answer 2

您可以將所有分割線存儲到ArrayList ：

private ArrayList<String[]> values;
@Override
protected void onCreate(Bundle savedInstanceState) {
    values = new ArrayList<String[]>();
    super.onCreate(savedInstanceState);
    setContentView(R.layout.highscore);
    readFile();
}


private void readFile() {
    // TODO Auto-generated method stub
    AssetManager manger;
    String line = null;

    try {
        manger = getAssets();
        InputStream is = manger.open("text.txt");
        InputStreamReader isr = new InputStreamReader(is);
        BufferedReader br = new BufferedReader(isr);
        while ((line = br.readLine()) != null) {
            values.add(line.split(","));
            //System.out.print(value);
        }
        br.close();

    } catch (IOException e1) {
        System.out.println("not good");
    }
}

Answer 3

你可以試試這個嗎

private void readFile() {
    // TODO Auto-generated method stub
    AssetManager manger;
    String line = null;

    try {
        manger = getAssets();
        InputStream is = manger.open("text.txt");
        InputStreamReader isr = new InputStreamReader(is);
        BufferedReader br = new BufferedReader(isr);
        while ((line = br.readLine()) != null) {
           String[] value = line.split(",");

           for(int i=0;i<value.length;i++)
               System.out.print("*************************************************"+value[i]);
        }
        br.close();


    } catch (IOException e1) {
        System.out.println("not good");

    }

}