System.IO

DriveInfo[] driveInfos = DriveInfo.GetDrives(); //返回所有逻辑驱动器
foreach (DriveInfo driveInfo in driveInfos)
{
    if (driveInfo.IsReady)
    {
        //磁盘已经准备好。
        string driveName = driveInfo.Name;
        string volumeLabel = driveInfo.VolumeLabel;
        long totalSize = driveInfo.TotalSize;
        long totalFreeSpace = driveInfo.TotalFreeSpace;
        long availableFreeSpace = driveInfo.AvailableFreeSpace;
        string driveFormat = driveInfo.DriveFormat; //NTFS, FAT32...
        DriveType driveType = driveInfo.DriveType;
    }
}