C# 获取磁盘容量

/// 获取指定驱动器的空间总大小(单位为B) 
        /// </summary> 
        /// <param name="str_HardDiskName">只需输入代表驱动器的字母即可 </param> 
        /// <returns> </returns> 
        public static long GetHardDiskSpace(string str_HardDiskName) 
        { 
            long totalSize= new long(); 
            str_HardDiskName=str_HardDiskName +":\\"; 
            System.IO.DriveInfo[] drives = System.IO.DriveInfo.GetDrives(); 
            foreach (System.IO.DriveInfo drive in drives) 
            { 
                if (drive.Name == str_HardDiskName) 
                { 
                    totalSize = drive.TotalSize; 
                } 
            } 
            return totalSize; 
        } 

        /// <summary> 
        /// 获取指定驱动器的剩余空间总大小(单位为B) 
        /// </summary> 
        /// <param name="str_HardDiskName">只需输入代表驱动器的字母即可 </param> 
        /// <returns> </returns> 
        public static long GetHardDiskFreeSpace(string str_HardDiskName) 
        { 
            long freeSpace = new long(); 
            str_HardDiskName = str_HardDiskName + ":\\"; 
            System.IO.DriveInfo[] drives = System.IO.DriveInfo.GetDrives(); 
            foreach (System.IO.DriveInfo drive in drives) 
            { 
                if (drive.Name == str_HardDiskName) 
                { 
                    freeSpace = drive.TotalFreeSpace; 
                } 
            }