【Android笔记】Android统计文件夹大小，删除文件夹下的所有文件方法

1、获取文件夹大小：

/**   
     * 获取文件夹大小   
     * @param file File实例   
     * @return long      
     */     
    public static long getFolderSize(java.io.File file){    
   
        long size = 0;    
        try {  
            java.io.File[] fileList = file.listFiles();     
            for (int i = 0; i < fileList.length; i++)     
            {     
                if (fileList[i].isDirectory())     
                {     
                    size = size + getFolderSize(fileList[i]);    
   
                }else{     
                    size = size + fileList[i].length();    
   
                }     
            }  
        } catch (Exception e) {  
            // TODO Auto-generated catch block  
            e.printStackTrace();  
        }     
       //return size/1048576;    
        return size;    
    }  

2、删除文件夹下所有文件：

/**   
     * 删除指定目录下文件及目录    
     * @param deleteThisPath   
     * @param filepath   
     * @return    
     */     
    public void deleteFolderFile(String filePath, boolean deleteThisPath) {     
        if (!TextUtils.isEmpty(filePath)) {     
            try {  
                File file = new File(filePath);     
                if (file.isDirectory()) {// 处理目录     
                    File files[] = file.listFiles();     
                    for (int i = 0; i < files.length; i++) {     
                        deleteFolderFile(files[i].getAbsolutePath(), true);     
                    }      
                }     
                if (deleteThisPath) {     
                    if (!file.isDirectory()) {// 如果是文件，删除     
                        file.delete();     
                    } else {// 目录     
                   if (file.listFiles().length == 0) {// 目录下没有文件或者目录，删除     
                            file.delete();     
                        }     
                    }     
                }  
            } catch (Exception e) {  
                // TODO Auto-generated catch block  
                e.printStackTrace();  
            }     
        }     
    }    

3、格式化文件夹大小单位：

/** 
     * 格式化单位 
     * @param size 
     * @return 
     */  
    public static String getFormatSize(double size) {  
        double kiloByte = size/1024;  
        if(kiloByte < 1) {  
            return size + "B";  
        }  
          
        double megaByte = kiloByte/1024;  
        if(megaByte < 1) {  
            BigDecimal result1 = new BigDecimal(Double.toString(kiloByte));  
            return result1.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "KB";  
        }  
          
        double gigaByte = megaByte/1024;  
        if(gigaByte < 1) {  
            BigDecimal result2  = new BigDecimal(Double.toString(megaByte));  
            return result2.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "MB";  
        }  
          
        double teraBytes = gigaByte/1024;  
        if(teraBytes < 1) {  
            BigDecimal result3 = new BigDecimal(Double.toString(gigaByte));  
            return result3.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "GB";  
        }  
        BigDecimal result4 = new BigDecimal(teraBytes);  
        return result4.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "TB";  
    }  

 参考原文：http://blog.csdn.net/nn955/article/details/36176429