SD卡相關的Android輔助類

    import java.io.File;


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

//SD卡相關的輔助類  
public class SDCardUtils  
{  
    private SDCardUtils()  
    {  
        /* cannot be instantiated */  
        throw new UnsupportedOperationException("cannot be instantiated");  
    }  

    /** 
     * 判斷SDCard是否可用 
     *  
     * @return 
     */  
    public static boolean isSDCardEnable()  
    {  
        return Environment.getExternalStorageState().equals(  
                Environment.MEDIA_MOUNTED);  

    }  

    /** 
     * 獲取SD卡路徑 
     *  
     * @return 
     */  
    public static String getSDCardPath()  
    {  
        return Environment.getExternalStorageDirectory().getAbsolutePath()  
                + File.separator;  
    }  

    /** 
     * 獲取SD卡的剩余容量 單位byte 
     *  
     * @return 
     */  
    public static long getSDCardAllSize()  
    {  
        if (isSDCardEnable())  
        {  
            StatFs stat = new StatFs(getSDCardPath());  
            // 獲取空閑的數據塊的數量  
            long availableBlocks = (long) stat.getAvailableBlocks() - 4;  
            // 獲取單個數據塊的大小（byte）  
            long freeBlocks = stat.getAvailableBlocks();  
            return freeBlocks * availableBlocks;  
        }  
        return 0;  
    }  

    /** 
     * 獲取指定路徑所在空間的剩余可用容量字節數，單位byte 
     *  
     * @param filePath 
     * @return 容量字節 SDCard可用空間，內部存儲可用空間 
     */  
    public static long getFreeBytes(String filePath)  
    {  
        // 如果是sd卡的下的路徑，則獲取sd卡可用容量  
        if (filePath.startsWith(getSDCardPath()))  
        {  
            filePath = getSDCardPath();  
        } else  
        {// 如果是內部存儲的路徑，則獲取內存存儲的可用容量  
            filePath = Environment.getDataDirectory().getAbsolutePath();  
        }  
        StatFs stat = new StatFs(filePath);  
        long availableBlocks = (long) stat.getAvailableBlocks() - 4;  
        return stat.getBlockSize() * availableBlocks;  
    }  

    /** 
     * 獲取系統存儲路徑 
     *  
     * @return 
     */  
    public static String getRootDirectoryPath()  
    {  
        return Environment.getRootDirectory().getAbsolutePath();  
    }  


}  </pre>