Android自助餐之文件存储

Android自助餐之文件存储

保存到应用目录下

[code]//写
FIle file = new File(context.getFilesDir(),"test.txt");//context.getCacheDir();为应用目录下的缓存目录
FileOutputStream fos=new FileOutputStream(file);
fos.write("test".getBytes());
fos.close();
//读
FileInputStream fis = new FileInputStream(file);
BufferedReader br = new BufferedReader(new InputStreamReader(fis));
String str=br.readLine();

保存到SD卡

[code]<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

[code]//判断SD卡状态
String state= Environment.getExternalStorageState();
if(state.equals(Environment.MEDAI_MOUNTED)){
    //操作文件
    File file = new File(Environment.getExteralStorageDirectory(),"test.txt");
}

获取SD卡大小

[code]File path = Environment.getExternalStorageDirectory();
StatFs stat = new StatFs(path.getPath());
long blockSize=stat.getBlockSize();//获取块大小
long totalBlocks=stats.getBlockCount();//获取总块数
long availableBlocks=stats.getAvailableBlocks();//获取可用块数

//计算大小
long totalSize= blockSize*totalBlocks;
long availSize=availableBlocks*totalBlocks;

//格式化字符串
String totalStr=Formatter.formatFileSize(context,totalSize);
String availStr=Formatter.formatFileSize(context,availSize);

获取内部存储空间

Environment.getExternalStorageDirectory()

Environment.getDataDirectory()