Android 判断SD卡是不是存在及容量查询

首先要在AndroidManifest.xml中增加SD卡访问权限

<!-- 在SDCard中创建与删除文件权限 -->  <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>  <!-- 往SDCard写入数据权限 -->  <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>   

private boolean ExistSDCard() {    if (android.os.Environment.getExternalStorageState().equals(      android.os.Environment.MEDIA_MOUNTED)) {     return true;    } else     return false;   }  

SD卡剩余空间

public long getSDFreeSize(){       //取得SD卡文件路径       File path = Environment.getExternalStorageDirectory();        StatFs sf = new StatFs(path.getPath());        //获取单个数据块的大小(Byte)       long blockSize = sf.getBlockSize();        //空闲的数据块的数量       long freeBlocks = sf.getAvailableBlocks();       //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     }   

public long getSDAllSize(){       //取得SD卡文件路径       File path = Environment.getExternalStorageDirectory();        StatFs sf = new StatFs(path.getPath());        //获取单个数据块的大小(Byte)       long blockSize = sf.getBlockSize();        //获取所有数据块数       long allBlocks = sf.getBlockCount();       //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     }