android io写入读取 txt 数据 封装

为了方便大家 在项目中得到一些   写入和读出 数据 

 

//生成写入的方法

 private void writeData() {
        String filePath = "/sdcard/Syb/";
        String fileName = "ImportantData.txt";
        writeTxtToFile("Wx:lcti1314", filePath, fileName);
    }

    // 将字符串写入到文本文件中
    private void writeTxtToFile(String strcontent, String filePath, String fileName) {
        //生成文件夹之后，再生成文件，不然会出错
        makeFilePath(filePath, fileName);

        String strFilePath = filePath + fileName;
        // 每次写入时，都换行写
        String strContent = strcontent + "\r\n";
        try {
            File file = new File(strFilePath);
            if (!file.exists()) {
                Log.d("TestFile", "Create the file:" + strFilePath);
                file.getParentFile().mkdirs();
                file.createNewFile();
            }
            RandomAccessFile raf = new RandomAccessFile(file, "rwd");
            raf.seek(file.length());
            raf.write(strContent.getBytes());
            raf.close();
        } catch (Exception e) {
            Log.e("TestFile", "Error on write File:" + e);
        }
    }

//生成文件

    private File makeFilePath(String filePath, String fileName) {
        File file = null;
        makeRootDirectory(filePath);
        try {
            file = new File(filePath + fileName);
            if (!file.exists()) {
                file.createNewFile();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return file;
    }

//生成文件夹

    private static void makeRootDirectory(String filePath) {
        File file = null;
        try {
            file = new File(filePath);
            if (!file.exists()) {
                file.mkdir();
            }
        } catch (Exception e) {
            Log.i("error:", e + "");
        }
    }

//生成读取的方法

 

//读取指定目录下的所有TXT文件的文件内容
private String getFileContent(File file) {
    String content = "";
    if (!file.isDirectory()) {  //检查此路径名的文件是否是一个目录(文件夹)
        if (file.getName().endsWith("txt")) {//文件格式为""文件
            try {
                InputStream instream = new FileInputStream(file);
                if (instream != null) {
                    InputStreamReader inputreader
                            = new InputStreamReader(instream, "UTF-8");
                    BufferedReader buffreader = new BufferedReader(inputreader);
                    String line = "";
                    //分行读取
                    while ((line = buffreader.readLine()) != null) {
                        content += line + "\n";
                    }
                    instream.close();//关闭输入流
                }
            } catch (java.io.FileNotFoundException e) {
                Log.d("TestFile", "The File doesn't not exist.");
            } catch (IOException e) {
                Log.d("TestFile", e.getMessage());
            }
        }
    }
    return content;
}

//  最后直接调用上面封装好的方法

//写入
writeData();

//读取

File file = new File("/sdcard/Syb/ImportantData.txt");
String fileContent = getFileContent(file);
Log.e("MainActivity", fileContent);