Android获取外部和内部存储空间总大小

Posted 2022-08-15 jdsjlzx

android.os下的StatFs类主要用来获取文件系统的状态，能够获取sd卡的大小和剩余空间，获取系统内部空间也就是/system的大小和剩余空间等等。

      看下读取sd卡的：

Java代码 
 void  readSDCard()    
         String state = Environment.getExternalStorageState();   
         if (Environment.MEDIA_MOUNTED.equals(state))    
             File sdcardDir = Environment.getExternalStorageDirectory();   
             StatFs sf = new  StatFs(sdcardDir.getPath());   
             long  blockSize = sf.getBlockSize();   
             long  blockCount = sf.getBlockCount();   
             long  availCount = sf.getAvailableBlocks();   
             Log.d("" ,  "block大小:" + blockSize+ ",block数目:" + blockCount+ ",总大小:" +blockSize*blockCount/ 1024 + "KB" );   
             Log.d("" ,  "可用的block数目：:" + availCount+ ",剩余空间:" + availCount*blockSize/ 1024 + "KB" );   
               
        
 void readSDCard() 
      String state = Environment.getExternalStorageState();
      if(Environment.MEDIA_MOUNTED.equals(state)) 
       File sdcardDir = Environment.getExternalStorageDirectory();
       StatFs sf = new StatFs(sdcardDir.getPath());
       long blockSize = sf.getBlockSize();
       long blockCount = sf.getBlockCount();
       long availCount = sf.getAvailableBlocks();
       Log.d("", "block大小:"+ blockSize+",block数目:"+ blockCount+",总大小:"+blockSize*blockCount/1024+"KB");
       Log.d("", "可用的block数目：:"+ availCount+",剩余空间:"+ availCount*blockSize/1024+"KB");
        
            然后看下读取系统内部空间的： Java代码 
 void  readSystem()    
         File root = Environment.getRootDirectory();   
         StatFs sf = new  StatFs(root.getPath());   
         long  blockSize = sf.getBlockSize();   
         long  blockCount = sf.getBlockCount();   
         long  availCount = sf.getAvailableBlocks();   
         Log.d("" ,  "block大小:" + blockSize+ ",block数目:" + blockCount+ ",总大小:" +blockSize*blockCount/ 1024 + "KB" );   
         Log.d("" ,  "可用的block数目：:" + availCount+ ",可用大小:" + availCount*blockSize/ 1024 + "KB" );   
        
 void readSystem() 
      File root = Environment.getRootDirectory();
   StatFs sf = new StatFs(root.getPath());
   long blockSize = sf.getBlockSize();
   long blockCount = sf.getBlockCount();
   long availCount = sf.getAvailableBlocks();
   Log.d("", "block大小:"+ blockSize+",block数目:"+ blockCount+",总大小:"+blockSize*blockCount/1024+"KB");
   Log.d("", "可用的block数目：:"+ availCount+",可用大小:"+ availCount*blockSize/1024+"KB");
            StatFs获取的都是以block为单位的，这里我解释一下block的概念： 1.硬件上的 block size, 应该是"sector size"，linux的扇区大小是512byte
 2.有文件系统的分区的block size, 是"block size"，大小不一，可以用工具查看
 3.没有文件系统的分区的block size，也叫“block size”，大小指的是1024 byte
 4.Kernel buffer cache 的block size, 就是"block size"，大部分PC是1024
 5.磁盘分区的"cylinder size"，用fdisk 可以查看。

      我们这里的block size是第二种情况，一般SD卡都是fat32的文件系统，block size是4096.

      这样就可以知道手机的内部存储空间和sd卡存储空间的总大小和可用大小了。