Android 获取文件大小

public class FileSizeUtil {
 public static final int SIZETYPE_B = 1;// 获取文件大小单位为B的double值
 public static final int SIZETYPE_KB = 2;// 获取文件大小单位为KB的double值
 public static final int SIZETYPE_MB = 3;// 获取文件大小单位为MB的double值
 public static final int SIZETYPE_GB = 4;// 获取文件大小单位为GB的double值
 /**
  * 获取文件指定文件的指定单位的大小
  * 
  * @param filePath
  *            文件路径
  * @param sizeType
  *            获取大小的类型1为B、2为KB、3为MB、4为GB
  * @return double值的大小
  */
 public static double getFileOrFilesSize(String filePath, int sizeType) {
  File file = new File(filePath);
  long blockSize = 0;
  try {
   if (file.isDirectory()) {
    blockSize = getFileSizes(file);
   } else {
    blockSize = getFileSize(file);
   }
  } catch (Exception e) {
   e.printStackTrace();
   Log.e("获取文件大小", "获取失败!");
  }
  return FormetFileSize(blockSize, sizeType);
 }
 /**
  * 调用此方法自动计算指定文件或指定文件夹的大小
  * 
  * @param filePath
  *            文件路径
  * @return 计算好的带B、KB、MB、GB的字符串
  */
 public static String getAutoFileOrFilesSize(String filePath) {
  File file = new File(filePath);
  long blockSize = 0;
  try {
   if (file.isDirectory()) {
    blockSize = getFileSizes(file);
   } else {
    blockSize = getFileSize(file);
   }
  } catch (Exception e) {
   e.printStackTrace();
   Log.e("获取文件大小", "获取失败!");
  }
  return FormetFileSize(blockSize);
 }
 /**
  * 获取指定文件大小
  * 
  * @param f
  * @return
  * @throws Exception
  */
 private static long getFileSize(File file) throws Exception {
  long size = 0;
  if (file.exists()) {
   FileInputStream fis = null;
   fis = new FileInputStream(file);
   size = fis.available();
  } else {
   file.createNewFile();
   Log.e("获取文件大小", "文件不存在!");
  }
  return size;
 }
 /**
  * 获取指定文件夹
  * 
  * @param f
  * @return
  * @throws Exception
  */
 private static long getFileSizes(File f) throws Exception {
  long size = 0;
  File flist[] = f.listFiles();
  for (int i = 0; i < flist.length; i++) {
   if (flist[i].isDirectory()) {
    size = size + getFileSizes(flist[i]);
   } else {
    size = size + getFileSize(flist[i]);
   }
  }
  return size;
 }
 /**
  * 转换文件大小
  * 
  * @param fileS
  * @return
  */
 private static String FormetFileSize(long fileS) {
  DecimalFormat df = new DecimalFormat("#.00");
  String fileSizeString = "";
  String wrongSize = "0B";
  if (fileS == 0) {
   return wrongSize;
  }
  if (fileS < 1024) {
   fileSizeString = df.format((double) fileS) + "B";
  } else if (fileS < 1048576) {
   fileSizeString = df.format((double) fileS / 1024) + "KB";
  } else if (fileS < 1073741824) {
   fileSizeString = df.format((double) fileS / 1048576) + "MB";
  } else {
   fileSizeString = df.format((double) fileS / 1073741824) + "GB";
  }
  return fileSizeString;
 }
 /**
  * 转换文件大小,指定转换的类型
  * 
  * @param fileS
  * @param sizeType
  * @return
  */
 private static double FormetFileSize(long fileS, int sizeType) {
  DecimalFormat df = new DecimalFormat("#.00");
  double fileSizeLong = 0;
  switch (sizeType) {
  case SIZETYPE_B:
   fileSizeLong = Double.valueOf(df.format((double) fileS));
   break;
  case SIZETYPE_KB:
   fileSizeLong = Double.valueOf(df.format((double) fileS / 1024));
   break;
  case SIZETYPE_MB:
   fileSizeLong = Double.valueOf(df.format((double) fileS / 1048576));
   break;
  case SIZETYPE_GB:
   fileSizeLong = Double.valueOf(df
     .format((double) fileS / 1073741824));
   break;
  default:
   break;
  }
  return fileSizeLong;
 }
}

转载地址https://my.oschina.net/u/1047462/blog/204627