Android 建立文件夹、生成文件并写入文本文件内容

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>

private void initData() {
String filePath = "/sdcard/Test/";
String fileName = "log.txt";

writeTxtToFile("txt content", filePath, fileName);
}

// 将字符串写入到文本文件中
public 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
public 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
public 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+"");
}
}