<!-- 在SDCard中创建与删除文件权限 -->  <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>  <!-- 往SDCard写入数据权限 -->  <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>   

    //SD是否存在    private boolean ExistSDCard() {        if (Environment.getExternalStorageState().equals(                Environment.MEDIA_MOUNTED)) {            return true;            } else                 return false;    }    //SD剩余空间    public long getSDFreeSize(){           //取得SD卡文件路径           File path = Environment.getExternalStorageDirectory();            StatFs sf = new StatFs(path.getPath());            //获取单个数据块的大小(Byte)           long blockSize = sf.getBlockSize();            //空闲的数据块的数量           long freeBlocks = sf.getAvailableBlocks();           //返回SD卡空闲大小           //return freeBlocks * blockSize;  //单位Byte           //return (freeBlocks * blockSize)/1024;   //单位KB           return (freeBlocks * blockSize)/1024 /1024; //单位MB      }    //SD总容量    public long getSDAllSize(){        //取得SD卡文件路径         File path = Environment.getExternalStorageDirectory();        StatFs sf = new StatFs(path.getPath());        //获取单个数据块的大小(Byte)        long blockSize = sf.getBlockSize();        //获取所有数据块数         long allBlocks = sf.getBlockCount();        //返回SD卡大小         //return allBlocks * blockSize; //单位Byte        //return (allBlocks * blockSize)/1024; //单位KB        return (allBlocks * blockSize)/1024/1024; //单位MB    }