Android读取sd卡

     public static String[] getStoragePaths() {
         List<String> pathsList = new ArrayList<String>();
         if (Build.VERSION.SDK_INT < Build.VERSION_CODES.GINGERBREAD) {
             File externalFolder = Environment.getExternalStorageDirectory();
             if (externalFolder != null) {
                 pathsList.add(externalFolder.getAbsolutePath());
             }
         } else {
             StorageManager storageManager = (StorageManager) mContext.getSystemService(Context.STORAGE_SERVICE);
             try {
                 Method method = StorageManager.class.getDeclaredMethod("getVolumePaths");
                 method.setAccessible(true);
                 Object result = method.invoke(storageManager);
                 if (result != null && result instanceof String[]) {
                     String[] paths = (String[]) result;
                     StatFs statFs;
                     for (String path : paths) {
                         if (!TextUtils.isEmpty(path) && new File(path).exists()) {
                             statFs = new StatFs(path);
                             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) {
                                 if (statFs.getBlockCountLong() * statFs.getBlockSizeLong() != ) {
                                     pathsList.add(path);
                                 }
                             }else{
                                 if (statFs.getBlockCount() * statFs.getBlockSize() != ) {
                                     pathsList.add(path);
                                 }
                             }
                         }
                     }
                 }
             } catch (Exception e) {
                 File externalFolder = Environment.getExternalStorageDirectory();
                 if (externalFolder != null) {
                     pathsList.add(externalFolder.getAbsolutePath());
                 }
             }
         }
         return pathsList.toArray(new String[pathsList.size()]);
     }