[Android]記憶卡容量?

import android.os.Environment;
import android.os.StatFs;

    /* 判斷記憶卡是否插入 */
    if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))
    {
      /* 取得SD CARD檔案路徑一般是/sdcard */
      File path = Environment.getExternalStorageDirectory();

      /* StatFs看檔案系統空間使用狀況 */
      StatFs statFs = new StatFs(path.getPath());
      /* Block的size */
      long blockSize = statFs.getBlockSize();
      /* 總Block數量 */
      long totalBlocks = statFs.getBlockCount();
      /* 已使用的Block數量 */
      long availableBlocks = statFs.getAvailableBlocks();

      String[] total = fileSize(totalBlocks * blockSize);
      String[] available = fileSize(availableBlocks * blockSize);

      ...

    } else if (Environment.getExternalStorageState().equals(
        Environment.MEDIA_REMOVED))
    {
      String text = "SD CARD已移除";
      ...
    }
  }