以编程方式查找网络位置

介绍

上周，我在互联网上正在努力寻找一个解决方案来解决一个有趣的问题，我正在构建一个“Windows资源管理器”的应用程序时遇到的问题。我无法访问通常在Windows资源管理器的“此PC”节点下看到的网络位置。

以编程方式查找网络位置

在环顾一个好时机之后，我终于找到了我需要的，并为那些有兴趣以编程方式浏览的人创建一个快速帮助库。

背景

为此，我们将只需要的C＃的工作知识，它可能是有帮助的如何浏览目录在C＃中的一些知识System.IO.DriveInfo和System.IO.DirectoryInfo类，静态方法和SHELL32 DLL。

走过这个过程

我遇到的第一个挑战是试图找到这些网络位置甚至存储的位置。他们必须是SOMEWHERE，最后。看了一会儿后，我终于发现他们实际上是存储在以下目录中的快捷方式：“ %AppData%/Microsoft/Windows/Network Shortcuts”

以编程方式查找网络位置

大！我们找到当前用户的“网络快捷方式”！现在，使用C＃以编程方式来访问这个位置。首先，我们不能简单地输入，new System.IO.DirectoryInfo("%AppData%/Microsoft/Windows/Network Shortcuts")因为System.IO.DirectoryInfo类（我们将用于浏览这些快捷方式）没有环境变量的任何概念。我们实际上必须输入new System.IO.DirectoryInfo("C:\Users\<<current_user>>\AppData\Roaming\Microsoft\Windows\Network Shortcuts") （<<current_user>>在Windows中替换为您的用户），尽管这将导致我们进入正确的位置，但这并不能补偿存储此数据的更改。我们实际想要使用的是枚举System.Environment.SpecialFolder。要完成这个，我们会进入 System.Environment.GetFolderPath(System.Environment.SpecialFolder.ApplicationData); 这是%AppData%我们在Windows资源管理器中使用的“ ”环境变量的编程相当的。使用System.IO.Path.Combine，我们可以创建完整的目录路径到我们的网络快捷方式：

隐藏复制代码


private static string NetworkLocationsPath { get; } = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "Microsoft", "Windows", "Network Shortcuts");

现在我们已经保存了NetworkShortcuts的位置并准备使用，接下来，我们需要遍历此目录中的每个快捷方式。为此，如上所述，我们将使用System.IO.DirectoryInfo该类。

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DirectoryInfo networkShortcuts = new DirectoryInfo(NetworkLocationsPath);

这些快捷方式不是文件快捷方式，而是文件夹快捷方式，因此，而不是使用System.IO.DirectoryInfo.GetFiles，我们将改为使用System.IO.DirectoryInfo.GetDirectories。现在用快速foreach语句，我们将遍历这个文件夹中的每个“目录”。

在查看DirectoryInfo类的一个实例中的其中一个快捷方式的每个属性和方法之后，遇到两个问题。首先，我不知道目录是否是快捷方式，其次，如果实例引用快捷方式，我无法获取快捷方式的目标。

以编程方式查找网络位置

看了一会儿后，我找到了两个解决方案来解决我的问题：

我发现的第一个解决方案是一个精采编码的自定义类，它将从快捷方式中提取目标路径（下面的代码），这个类的好处是我不需要引用Shell32 dll。我将类稍微操作为一个静态类，并隐藏了一些暴露的类和属性，我觉得不一定需要暴露。以下不是我的代码，我已经寻找原始的来源，我把代码从而找不到 - 如果你碰巧知道，请让我知道，我会相应地更新这篇文章。

隐藏收缩

复制代码



using System; using System.Runtime.InteropServices; using System.Text; internal static class ShortcutResolver


{ #region Signatures imported from http://pinvoke.net  [DllImport("shfolder.dll", CharSet = CharSet.Auto)] private static extern int SHGetFolderPath(IntPtr hwndOwner, int nFolder, IntPtr hToken, int dwFlags, StringBuilder lpszPath);

 

    [Flags()] enum SLGP_FLAGS


    { /// <summary>Retrieves the standard short (8.3 format) file name</summary>  SLGP_SHORTPATH = 0x1, /// <summary>Retrieves the Universal Naming Convention (UNC) path name of the file</summary>  SLGP_UNCPRIORITY = 0x2, /// <summary>Retrieves the raw path name. A raw path is something that might not exist and may include environment variables that need to be expanded</summary>  SLGP_RAWPATH = 0x4


    }

 

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)] struct WIN32_FIND_DATAW


    { public uint dwFileAttributes; public long ftCreationTime; public long ftLastAccessTime; public long ftLastWriteTime; public uint nFileSizeHigh; public uint nFileSizeLow; public uint dwReserved0; public uint dwReserved1;


        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)] public string cFileName;


        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 14)] public string cAlternateFileName;


    }

 

    [Flags()] enum SLR_FLAGS


    { /// <summary>  /// Do not display a dialog box if the link cannot be resolved. When SLR_NO_UI is set,  /// the high-order word of fFlags can be set to a time-out value that specifies the  /// maximum amount of time to be spent resolving the link. The function returns if the  /// link cannot be resolved within the time-out duration. If the high-order word is set  /// to zero, the time-out duration will be set to the default value of 3,000 milliseconds  /// (3 seconds). To specify a value, set the high word of fFlags to the desired time-out  /// duration, in milliseconds.  /// </summary>  SLR_NO_UI = 0x1, /// <summary>Obsolete and no longer used</summary>  SLR_ANY_MATCH = 0x2, /// <summary>If the link object has changed, update its path and list of identifiers.  /// If SLR_UPDATE is set, you do not need to call IPersistFile::IsDirty to determine  /// whether or not the link object has changed.</summary>  SLR_UPDATE = 0x4, /// <summary>Do not update the link information</summary>  SLR_NOUPDATE = 0x8, /// <summary>Do not execute the search heuristics</summary>  SLR_NOSEARCH = 0x10, /// <summary>Do not use distributed link tracking</summary>  SLR_NOTRACK = 0x20, /// <summary>Disable distributed link tracking. By default, distributed link tracking tracks  /// removable media across multiple devices based on the volume name. It also uses the  /// Universal Naming Convention (UNC) path to track remote file systems whose drive letter  /// has changed. Setting SLR_NOLINKINFO disables both types of tracking.</summary>  SLR_NOLINKINFO = 0x40, /// <summary>Call the Microsoft Windows Installer</summary>  SLR_INVOKE_MSI = 0x80


    } /// <summary>The IShellLink interface allows Shell links to be created, modified, and resolved</summary>  [ComImport(), InterfaceType(ComInterfaceType.InterfaceIsIUnknown), Guid("000214F9-0000-0000-C000-000000000046")] interface IShellLinkW


    { /// <summary>Retrieves the path and file name of a Shell link object</summary>  void GetPath([Out(), MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszFile, int cchMaxPath, out WIN32_FIND_DATAW pfd, SLGP_FLAGS fFlags); /// <summary>Retrieves the list of item identifiers for a Shell link object</summary>  void GetIDList(out IntPtr ppidl); /// <summary>Sets the pointer to an item identifier list (PIDL) for a Shell link object.</summary>  void SetIDList(IntPtr pidl); /// <summary>Retrieves the description string for a Shell link object</summary>  void GetDescription([Out(), MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszName, int cchMaxName); /// <summary>Sets the description for a Shell link object. The description can be any application-defined string</summary>  void SetDescription([MarshalAs(UnmanagedType.LPWStr)] string pszName); /// <summary>Retrieves the name of the working directory for a Shell link object</summary>  void GetWorkingDirectory([Out(), MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszDir, int cchMaxPath); /// <summary>Sets the name of the working directory for a Shell link object</summary>  void SetWorkingDirectory([MarshalAs(UnmanagedType.LPWStr)] string pszDir); /// <summary>Retrieves the command-line arguments associated with a Shell link object</summary>  void GetArguments([Out(), MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszArgs, int cchMaxPath); /// <summary>Sets the command-line arguments for a Shell link object</summary>  void SetArguments([MarshalAs(UnmanagedType.LPWStr)] string pszArgs); /// <summary>Retrieves the hot key for a Shell link object</summary>  void GetHotkey(out short pwHotkey); /// <summary>Sets a hot key for a Shell link object</summary>  void SetHotkey(short wHotkey); /// <summary>Retrieves the show command for a Shell link object</summary>  void GetShowCmd(out int piShowCmd); /// <summary>Sets the show command for a Shell link object. The show command sets the initial show state of the window.</summary>  void SetShowCmd(int iShowCmd); /// <summary>Retrieves the location (path and index) of the icon for a Shell link object</summary>  void GetIconLocation([Out(), MarshalAs(UnmanagedType.LPWStr)] StringBuilder pszIconPath, int cchIconPath, out int piIcon); /// <summary>Sets the location (path and index) of the icon for a Shell link object</summary>  void SetIconLocation([MarshalAs(UnmanagedType.LPWStr)] string pszIconPath, int iIcon); /// <summary>Sets the relative path to the Shell link object</summary>  void SetRelativePath([MarshalAs(UnmanagedType.LPWStr)] string pszPathRel, int dwReserved); /// <summary>Attempts to find the target of a Shell link, even if it has been moved or renamed</summary>  void Resolve(IntPtr hwnd, SLR_FLAGS fFlags); /// <summary>Sets the path and file name of a Shell link object</summary>  void SetPath([MarshalAs(UnmanagedType.LPWStr)] string pszFile);

 

    }

 

    [ComImport, Guid("0000010c-0000-0000-c000-000000000046"),


    InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] private interface IPersist


    {


        [PreserveSig] void GetClassID(out Guid pClassID);


    }

 

    [ComImport, Guid("0000010b-0000-0000-C000-000000000046"),


    InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] private interface IPersistFile : IPersist


    { new void GetClassID(out Guid pClassID);


        [PreserveSig] int IsDirty();

 

        [PreserveSig] void Load([In, MarshalAs(UnmanagedType.LPWStr)] string pszFileName, uint dwMode);

 

        [PreserveSig] void Save([In, MarshalAs(UnmanagedType.LPWStr)] string pszFileName,


            [In, MarshalAs(UnmanagedType.Bool)] bool fRemember);

 

        [PreserveSig] void SaveCompleted([In, MarshalAs(UnmanagedType.LPWStr)] string pszFileName);

 

        [PreserveSig] void GetCurFile([In, MarshalAs(UnmanagedType.LPWStr)] string ppszFileName);


    } const uint STGM_READ = 0; const int MAX_PATH = 260; // CLSID_ShellLink from ShlGuid.h [


        ComImport(),


        Guid("00021401-0000-0000-C000-000000000046")


    ] private class ShellLink


    {


    } #endregion  public static string GetPath(string filename)


    {


        ShellLink link = new ShellLink();


        ((IPersistFile)link).Load(filename, STGM_READ); // TODO: if I can get hold of the hwnd call resolve first. This handles moved and renamed files. // ((IShellLinkW)link).Resolve(hwnd, 0) StringBuilder sb = new StringBuilder(MAX_PATH);


        WIN32_FIND_DATAW data = new WIN32_FIND_DATAW();


        ((IShellLinkW)link).GetPath(sb, sb.Capacity, out data, 0); return sb.ToString();


    }

}

我发现的第二个解决方案是通过Shell32在Microsoft Shell控件和自动化 COM类型库中引用该库。要在Visual Studio中添加此项目，请在项目中右键单击“ 引用”，单击“ 添加引用”，展开“ 参考管理器 ”左侧的COM选项，单击“ 类型库”，向下滚动到“ Microsoft Shell控件和自动化”，检查复选框，然后单击确定。

以编程方式查找网络位置

现在，要访问这些信息，我们将使用下面的代码。我设置了这个代码来使用静态方法和变量，以便将它并入到稍后将要介绍的助手类中。

隐藏收缩

复制代码



private static string NetworkLocationsPath { get; } = System.IO.Path.Combine(System.Environment.GetFolderPath(System.Environment.SpecialFolder.ApplicationData), "Microsoft", "Windows", "Network Shortcuts"); #region Shell Support  private static Shell32.Folder _networkLocationsFolder; private static Shell32.Folder NetworkLocationsFolder


{ get { if (_networkLocationsFolder == null)


        {


            Shell32.Shell shell = new Shell32.Shell();


            _networkLocationsFolder = shell.NameSpace(NetworkLocationsPath);


        } return _networkLocationsFolder;


    }


} private static string GetShortCutPath(string name)


{ try {


        Shell32.FolderItem folderItem = NetworkLocationsFolder.ParseName(name); if (folderItem == null || !folderItem.IsLink) return null;

 

        Shell32.ShellLinkObject link = (Shell32.ShellLinkObject)folderItem.GetLink; return link.Path;


    } catch { return null;


    }


} #endregion

使用外推路径信息，我可以System.IO.DirectoryInfo使用该路径创建一个新的实例。

以上是方便的，但是，我想把所有这一切都包装成一个简单的类，它将类似于System.IO.DriveInfo类，这将允许我获取所有的网络位置，并处理所有的名称解析，快捷方式目标提取和有效为我提供一站式服务。

我决定在System.IO命名空间中创建这个类，尽管你可以随意改变，但是你认为合适。

隐藏收缩

复制代码



using System.Runtime.InteropServices; using System.Runtime.Serialization; using System.Security; namespace System.IO


{ /// <summary>  /// Provides access to information on a Network Location.  /// </summary>  [ComVisible(true)] public sealed class NetworkLocationInfo : ISerializable


    { /// <summary>  /// Gets a value that indicates whether a network location is ready.  /// </summary>  public bool IsReady { get { return RootDirectory.Exists; } } /// <summary>  /// Gets a value that indicates whether a network location is mapped.  /// </summary>  public bool IsMapped { get { return ShortcutFile.Exists; } } /// <summary>  /// Gets the name of the share, such as \\192.168.100.1\data.  /// </summary>  public string Name { get { return RootDirectory.FullName; } } /// <summary>  /// Gets the share name on the server  /// </summary>  public string ShareName { get; } /// <summary>  /// Gets the name or IP address of the server  /// </summary>  public string ServerName { get; } /// <summary>  /// Gets the share label of a network location  /// </summary>  public string ShareLabel


        { get { return ShortcutFile.Name; } set { if (!ShortcutFile.Exists) throw new FileNotFoundException("Cannot find the network location shortcut file");

 

                ShortcutFile.MoveTo(Path.Combine(ShortcutFile.Parent.FullName, value));


            }


        } /// <summary>  /// Gets the root directory of a network location.  /// </summary>  public DirectoryInfo RootDirectory { get; } private DirectoryInfo _shortcutFile; private DirectoryInfo ShortcutFile { get { if (_shortcutFile == null)


                    _shortcutFile = FindShortCutFile(); return _shortcutFile;


            }


        } /// <summary>  /// Provides access to information on the specified network location.  /// </summary>  [SecuritySafeCritical] public NetworkLocationInfo(string networkLocationPath)


            : this(networkLocationPath, null) { } private NetworkLocationInfo(string networkLocationPath, DirectoryInfo shortcutFile)


        { if (string.IsNullOrWhiteSpace(networkLocationPath)) throw new ArgumentNullException(nameof(networkLocationPath)); if (!networkLocationPath.StartsWith("\\\\")) throw new ArgumentException("The UNC path should be of the form \\\\server\\share"); string root = networkLocationPath.TrimStart("\\"); // TODO: This needs to use a apostrophe (single quote) instead of a double quote, but does not format properly in the article with a single quote. int i = root.IndexOf("\\"); if (i < 0 || i + 1 == root.Length) throw new ArgumentException("The UNC path should be of the form \\\\server\\share");

 

            ServerName = root.Substring(0, i);


            root = root.Substring(i + 1);


            i = root.IndexOf("\\");


            ShareName = i < 0 ? root : root.Substring(0, i); if (string.IsNullOrWhiteSpace(ShareName)) throw new ArgumentException("The UNC path should be of the form \\\\server\\share");

 

            RootDirectory = new DirectoryInfo(string.Concat("\\\\", ServerName, "\\", ShareName));

 

            _shortcutFile = shortcutFile ?? FindShortCutFile();


        } private DirectoryInfo FindShortCutFile()


        {


            DirectoryInfo network = new DirectoryInfo(NetworkLocationsPath); foreach (DirectoryInfo dir in network.EnumerateDirectories())


            { string path = GetShortCutPath(dir.Name); if (string.Equals(RootDirectory.FullName, path, StringComparison.OrdinalIgnoreCase)) return dir;


            } return new DirectoryInfo(Path.Combine(NetworkLocationsPath, string.Concat(ShareName, " (", ServerName, ")")));


        } #region ISerializable methods  /// <summary>  /// Creates a new instance through deserialization  /// </summary>  internal NetworkLocationInfo(SerializationInfo info, StreamingContext context)


        { if (info == null) throw new ArgumentNullException(nameof(info));

 

            ShareName = info.GetString(nameof(ShareName));


            ServerName = info.GetString(nameof(ServerName));


            RootDirectory = new DirectoryInfo(info.GetString(nameof(RootDirectory)));


            _shortcutFile = new DirectoryInfo(info.GetString(nameof(ShortcutFile)));


        } void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)


        { if (info == null) throw new ArgumentNullException(nameof(info));

 

            info.AddValue(nameof(ShareName), ShareName);


            info.AddValue(nameof(ServerName), ServerName);


            info.AddValue(nameof(RootDirectory), RootDirectory.FullName);


            info.AddValue(nameof(ShortcutFile), ShortcutFile.FullName);


        } #endregion  #region Object methods  public override string ToString()


        { return Name;


        } public override bool Equals(object obj)


        { if (obj == null) return false; if (obj is NetworkLocationInfo) return string.Equals(((NetworkLocationInfo)obj).Name, Name, StringComparison.OrdinalIgnoreCase); return false;


        } public override int GetHashCode()


        { return Name.GetHashCode();


        } #endregion  #region Static Methods  private static string NetworkLocationsPath { get; } = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "Microsoft", "Windows", "Network Shortcuts"); #region Shell Support  private static Shell32.Folder _networkLocationsFolder; private static Shell32.Folder NetworkLocationsFolder


        { get { if (_networkLocationsFolder == null)


                {


                    Shell32.Shell shell = new Shell32.Shell();


                    _networkLocationsFolder = shell.NameSpace(NetworkLocationsPath);


                } return _networkLocationsFolder;


            }


        } private static string GetShortCutPath(string name)


        { try {


                Shell32.FolderItem folderItem = NetworkLocationsFolder?.ParseName(name); if (folderItem == null || !folderItem.IsLink) return null;

 

                Shell32.ShellLinkObject link = (Shell32.ShellLinkObject)folderItem.GetLink; return link.Path;


            } catch { return null;


            }


        } #endregion  /// <summary>  /// Gets all of the network locations found.  /// </summary>  public static NetworkLocationInfo[] GetNetworkLocations()


        { if (NetworkLocationsFolder == null) return new NetworkLocationInfo[] { };

 

            DirectoryInfo networkShortcuts = new DirectoryInfo(NetworkLocationsPath);

 

            DirectoryInfo[] subDirectories = networkShortcuts.GetDirectories();

 

            NetworkLocationInfo[] locations = new NetworkLocationInfo[subDirectories.Length]; if (subDirectories.Length == 0) return locations; int i = 0; foreach (DirectoryInfo dir in subDirectories)


            { string networkLocationPath = GetShortCutPath(dir.Name); if (string.IsNullOrWhiteSpace(networkLocationPath)) continue; try {


                    NetworkLocationInfo info = new NetworkLocationInfo(networkLocationPath, dir);

 

                    locations[i++] = info;


                } catch { continue; }


            } if (i < locations.Length)


                Array.Resize(ref locations, i); return locations;


        } #endregion  }

}

有了这个助手类，我们现在可以通过简单的调用浏览我们的网络位置快捷方式 NetworkLocationInfo.GetNetworkLocations()

对于我的用途，我正在创建一个具有所有网络位置的树，下面是我如何实现这个帮助类。

隐藏复制代码



// Load Network Locations foreach (NetworkLocationInfo n in NetworkLocationInfo.GetNetworkLocations())


{ if (!n.IsReady) continue;

 

    TreeNode aNode = new TreeNode(n.ShareLabel, (int)ImageKeys.NetworkDrive, (int)ImageKeys.NetworkDrive);

 

    aNode.Tag = n.RootDirectory;


    aNode.ImageKey = "network-location"; try {


        GetDirectories(n.RootDirectory.EnumerateDirectories(), aNode);


        nodeToAddTo.Nodes.Add(aNode);


    } catch { }

}

享受快乐编码！

以编程方式查找网络位置

介绍

背景

走过这个过程

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