SD卡

Android 判断SD卡是否存在及容量查询的简单方法如下：

首先要在AndroidManifest.xml中增加SD卡访问权限

   

Ø      在SDCard中创建与删除文件权限

<uses-permission     android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>

 

Ø      往SDCard写入数据权限

<uses-permissionandroid:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

 

Ø      SD卡是否存在

private booleanExistSDCard() {

     if(android.os.Environment.getExternalStorageState().equals(

      android.os.Environment.MEDIA_MOUNTED)) {

      return true;

     } else

      return false;

    }

 

Ø      SD卡剩余空间

public long getSDFreeSize(){

      File path =Environment.getExternalStorageDirectory();//路径

      StatFs sf = new StatFs(path.getPath());

      long blockSize = sf.getBlockSize();//获取单个数据块的大小

      long freeBlocks =sf.getAvailableBlocks();//空闲数据块数量

      //返回SD卡空闲大小

      //return freeBlocks * blockSize;  //单位Byte

      //return (freeBlocks *blockSize)/1024;   //单位KB

      return (freeBlocks * blockSize)/1024/1024; //单位MB

    } 

 

Ø      SD卡总容量

public longgetSDAllSize(){ 

     File path =Environment.getExternalStorageDirectory();  

     StatFs sf = newStatFs(path.getPath());  

     long blockSize = sf.getBlockSize();  

     long allBlocks = sf.getBlockCount();  //获取所有数据块数  

     //返回SD卡大小  

     //return allBlocks * blockSize; //单位Byte  

     //return (allBlocks * blockSize)/1024; //单位KB  

     return (allBlocks * blockSize)/1024/1024;//单位MB  

   }