Android 记录一个好用的文件存储操作工具类SDCardHelper
16lz
2021-01-23
public class SDCardHelper { // 判断SD卡是否被挂载 public static boolean isSDCardMounted() { // return Environment.getExternalStorageState().equals("mounted"); return Environment.getExternalStorageState().equals( Environment.MEDIA_MOUNTED); } // 获取SD卡的根目录 public static String getSDCardBaseDir() { if (isSDCardMounted()) { return Environment.getExternalStorageDirectory().getAbsolutePath(); } return null; } // 获取SD卡的完整空间大小，返回MB public static long getSDCardSize() { if (isSDCardMounted()) { StatFs fs = new StatFs(getSDCardBaseDir()); long count = fs.getBlockCountLong(); long size = fs.getBlockSizeLong(); return count * size / 1024 / 1024; } return 0; } // 获取SD卡的剩余空间大小 public static long getSDCardFreeSize() { if (isSDCardMounted()) { StatFs fs = new StatFs(getSDCardBaseDir()); long count = fs.getFreeBlocksLong(); long size = fs.getBlockSizeLong(); return count * size / 1024 / 1024; } return 0; } // 获取SD卡的可用空间大小 public static long getSDCardAvailableSize() { if (isSDCardMounted()) { StatFs fs = new StatFs(getSDCardBaseDir()); long count = fs.getAvailableBlocksLong(); long size = fs.getBlockSizeLong(); return count * size / 1024 / 1024; } return 0; } // 往SD卡的公有目录下保存文件 public static boolean saveFileToSDCardPublicDir(byte[] data, String type, String fileName) { BufferedOutputStream bos = null; if (isSDCardMounted()) { File file = Environment.getExternalStoragePublicDirectory(type); try { bos = new BufferedOutputStream(new FileOutputStream(new File(file, fileName))); bos.write(data); bos.flush(); return true; } catch (Exception e) { e.printStackTrace(); } finally { try { bos.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return false; } // 往SD卡的自定义目录下保存文件 public static boolean saveFileToSDCardCustomDir(byte[] data, String dir, String fileName) { BufferedOutputStream bos = null; if (isSDCardMounted()) { File file = new File(getSDCardBaseDir() + File.separator + dir); if (!file.exists()) { file.mkdirs();// 递归创建自定义目录 } try { bos = new BufferedOutputStream(new FileOutputStream(new File(file, fileName))); bos.write(data); bos.flush(); return true; } catch (Exception e) { e.printStackTrace(); } finally { try { bos.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return false; } // 往SD卡的私有Files目录下保存文件 public static boolean saveFileToSDCardPrivateFilesDir(byte[] data, String type, String fileName, Context context) { BufferedOutputStream bos = null; if (isSDCardMounted()) { File file = context.getExternalFilesDir(type); try { bos = new BufferedOutputStream(new FileOutputStream(new File(file, fileName))); bos.write(data); bos.flush(); return true; } catch (Exception e) { e.printStackTrace(); } finally { try { bos.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return false; } // 往SD卡的私有Cache目录下保存文件 public static boolean saveFileToSDCardPrivateCacheDir(byte[] data, String fileName, Context context) { BufferedOutputStream bos = null; if (isSDCardMounted()) { File file = context.getExternalCacheDir(); try { bos = new BufferedOutputStream(new FileOutputStream(new File(file, fileName))); bos.write(data); bos.flush(); return true; } catch (Exception e) { e.printStackTrace(); } finally { try { bos.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } return false; } // 保存bitmap图片到SDCard的私有Cache目录 public static boolean saveBitmapToSDCardPrivateCacheDir(Bitmap bitmap, String fileName, Context context) { if (isSDCardMounted()) { BufferedOutputStream bos = null; // 获取私有的Cache缓存目录 File file = context.getExternalCacheDir(); try { bos = new BufferedOutputStream(new FileOutputStream(new File(file, fileName))); if (fileName != null && (fileName.contains(".png") || fileName.contains(".PNG"))) { bitmap.compress(Bitmap.CompressFormat.PNG, 100, bos); } else { bitmap.compress(Bitmap.CompressFormat.JPEG, 100, bos); } bos.flush(); } catch (Exception e) { e.printStackTrace(); } finally { if (bos != null) { try { bos.close(); } catch (IOException e) { e.printStackTrace(); } } } return true; } else { return false; } } // 从SD卡获取文件 public static byte[] loadFileFromSDCard(String fileDir) { BufferedInputStream bis = null; ByteArrayOutputStream baos = new ByteArrayOutputStream(); try { bis = new BufferedInputStream(new FileInputStream(new File(fileDir))); byte[] buffer = new byte[8 * 1024]; int c = 0; while ((c = bis.read(buffer)) != -1) { baos.write(buffer, 0, c); baos.flush(); } return baos.toByteArray(); } catch (Exception e) { e.printStackTrace(); } finally { try { baos.close(); bis.close(); } catch (IOException e) { e.printStackTrace(); } } return null; } // 从SDCard中寻找指定目录下的文件，返回Bitmap public Bitmap loadBitmapFromSDCard(String filePath) { byte[] data = loadFileFromSDCard(filePath); if (data != null) { Bitmap bm = BitmapFactory.decodeByteArray(data, 0, data.length); if (bm != null) { return bm; } } return null; } // 获取SD卡公有目录的路径 public static String getSDCardPublicDir(String type) { return Environment.getExternalStoragePublicDirectory(type).toString(); } // 获取SD卡私有Cache目录的路径 public static String getSDCardPrivateCacheDir(Context context) { return context.getExternalCacheDir().getAbsolutePath(); } // 获取SD卡私有Files目录的路径 public static String getSDCardPrivateFilesDir(Context context, String type) { return context.getExternalFilesDir(type).getAbsolutePath(); } public static boolean isFileExist(String filePath) { File file = new File(filePath); return file.isFile(); } // 从sdcard中删除文件 public static boolean removeFileFromSDCard(String filePath) { File file = new File(filePath); if (file.exists()) { try { file.delete(); return true; } catch (Exception e) { return false; } } else { return false; } }}更多相关文章
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