//調用windows API獲取磁盤空閑空間//導入庫[DllImport("kernel32.dll", CharSet = CharSet.Auto)]static extern bool GetDiskFreeSpace([MarshalAs(UnmanagedType.LPTStr)]string rootPathName,ref int sectorsPerCluster, ref int bytesPerSector, ref int numberOfFreeClusters, ref int totalNumbeOfClusters);

/// <summary>/// 獲取指定路徑的大小/// </summary>/// <param name="dirPath">路徑</param>/// <returns></returns>public static long GetDirectoryLength(string dirPath){long len = 0;//判斷該路徑是否存在（是否為文件夾）if (!Directory.Exists(dirPath)){//查詢文件的大小len = FileSize(dirPath);}else{//定義一個DirectoryInfo對象DirectoryInfo di = new DirectoryInfo(dirPath);//通過GetFiles方法，獲取di目錄中的所有文件的大小foreach (FileInfo fi in di.GetFiles()){len += fi.Length;}//獲取di中所有的文件夾，并存到一個新的對象數組中，以進行遞歸DirectoryInfo[] dis = di.GetDirectories();if (dis.Length > 0){for (int i = 0; i < dis.Length; i++){len += GetDirectoryLength(dis[i].FullName);}}}return len;}/// <summary>/// 獲取指定路徑的占用空間/// </summary>/// <param name="dirPath">路徑</param>/// <returns></returns>public static long GetDirectorySpace(string dirPath){//返回值long len = 0;//判斷該路徑是否存在（是否為文件夾）if (!Directory.Exists(dirPath)){//如果是文件，則調用len = FileSpace(dirPath);}else{//定義一個DirectoryInfo對象DirectoryInfo di = new DirectoryInfo(dirPath);//本機的簇值long clusterSize = GetClusterSize(di);//遍歷目錄下的文件，獲取總占用空間foreach (FileInfo fi in di.GetFiles()){//文件大小除以簇，余若不為0if (fi.Length % clusterSize != 0){decimal res = fi.Length / clusterSize;//文件大小除以簇，取整數加1。為該文件占用簇的值int clu = Convert.ToInt32(Math.Ceiling(res)) + 1;long result = clusterSize * clu;len += result;}else{//余若為0，則占用空間等于文件大小len += fi.Length;}}//獲取di中所有的文件夾，并存到一個新的對象數組中，以進行遞歸DirectoryInfo[] dis = di.GetDirectories();if (dis.Length > 0){for (int i = 0; i < dis.Length; i++){len += GetDirectorySpace(dis[i].FullName);}}}return len;}//所給路徑中所對應的文件大小public static long FileSize(string filePath){//定義一個FileInfo對象，是指與filePath所指向的文件相關聯，以獲取其大小FileInfo fileInfo = new FileInfo(filePath);return fileInfo.Length;}//所給路徑中所對應的文件占用空間public static long FileSpace(string filePath){long temp = 0;//定義一個FileInfo對象，是指與filePath所指向的文件相關聯，以獲取其大小FileInfo fileInfo = new FileInfo(filePath);long clusterSize = GetClusterSize(fileInfo);if (fileInfo.Length % clusterSize != 0){decimal res = fileInfo.Length / clusterSize;int clu = Convert.ToInt32(Math.Ceiling(res)) + 1;temp = clusterSize * clu;}else{return fileInfo.Length;}return temp;}public static DiskInfo GetDiskInfo(string rootPathName){DiskInfo diskInfo = new DiskInfo();int sectorsPerCluster = 0, bytesPerSector = 0, numberOfFreeClusters = 0, totalNumberOfClusters = 0;GetDiskFreeSpace(rootPathName, ref sectorsPerCluster, ref bytesPerSector, ref numberOfFreeClusters, ref totalNumberOfClusters);//每簇的扇區數diskInfo.SectorsPerCluster = sectorsPerCluster;//每扇區字節diskInfo.BytesPerSector = bytesPerSector;return diskInfo;}//// <summary>/// 結構。硬盤信息/// </summary>public struct DiskInfo{public string RootPathName;//每簇的扇區數public int SectorsPerCluster;//每扇區字節public int BytesPerSector;public int NumberOfFreeClusters;public int TotalNumberOfClusters;}/// <summary>/// 獲取每簇的字節/// </summary>/// <param name="file">指定文件</param>/// <returns></returns>public static long GetClusterSize(FileInfo file){long clusterSize = 0;DiskInfo diskInfo = new DiskInfo();diskInfo = GetDiskInfo(file.Directory.Root.FullName);clusterSize = (diskInfo.BytesPerSector * diskInfo.SectorsPerCluster);return clusterSize;}/// <summary>/// 獲取每簇的字節/// </summary>/// <param name="dir">指定目錄</param>/// <returns></returns>public static long GetClusterSize(DirectoryInfo dir){long clusterSize = 0;DiskInfo diskInfo = new DiskInfo();diskInfo = GetDiskInfo(dir.Root.FullName);clusterSize = (diskInfo.BytesPerSector * diskInfo.SectorsPerCluster);return clusterSize;}