直接上代码~
注意权限
1.写入数据
private void writeData() {
String filePath = "/sdcard/Gyt/";
String fileName = "data.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 + "");
}
}
2.读取数据
//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;
}
3.代码调用
代码调用.png
2.效果展示
效果展示.gif
