C# Tips之程序关联文件

技术2025-11-20 2

写在前面

C# Tips是博主开启的第一个项目，以C#为示例语言，旨在普及编程技巧、经典算法以及计算机视觉、图形学知识。

关联文件的意义

想必各位同学在双击打开非txt的文本文件时通常会遇到这样的困扰：因为以.cue为后缀的文件并未与电脑中的任何程序关联，所以无法直接打开文件，选择一个能够打开文件的软件其实就是将cue文件与之进行关联。好处显而易见，就是凡是cue文件都可以通过指定软件直接双击打开。当然除此之外，文件如果还带有特定的图标，那么更能提升文件的逼格。

修改注册表

文件的关联信息存储在注册表（Win+R再输入regedit即可打开注册表）中，无论是修改默认程序还是指定程序，其本质都是修改了注册表信息。自定义文件关联信息通常存储在HKEY_CLASSES_ROOT结点下：

第一项为*，其含义为通用的关联方式，换句话说就是可以利用一个软件打开所有文件；其他项则是特定后缀文件的关联方式。

通用关联

对于第一种情况，以Sublime Text软件（可以正常打开所有纯文本格式文件）为例，需要实现如下图所示的功能，即右键cue文件，然后点击Open With Sublime Text，利用Sublime Text打开cue文件。具体修改注册表的方法为：在*结点下的shell结点中添加结点Sublime Text，然后修改默认项数据为Open With Sublime Text，然后在Sublime Text结点下添加结点command，修改默认项数据为"D:\Sublime Text\sublime_text.exe"<“Sublime Text程序所在路径”> “%1”。

特定关联

对于第二种情况，最普遍的需求是将自己编写的文件格式关联到自己编写的程序上。拿博主之前写过的一个三维重建系统MeasureMan举例，该系统的工程文件是以.msm为后缀的自定义文本文件，如下图所示msm文件与程序图标相同，且通过双击可以直接打开msm文件。具体修改注册表的方法为：在HKEY_CLASSES_ROOT结点下添加.msm/Shell/Open/Command，然后在.msm结点中添加File Type项并填入数据msm File，最后修改Command结点的默认项数据为<“MeasureMan程序所在路径”> “%1”。

程序关联文件代码

.NET提供了Registry、RegistryKey等类可以很方便地对注册表进行操作，如下代码实现了在HKEY_CLASSES_ROOT结点下添加结点的过程，注意添加或修改注册表项必须先获得管理员权限：如果结点不存在直接添加，关联当前程序路径；如果结点存在但当前程序路径与已有路径不同，则替换程序路径。

try { RegistryKey mainkey = Registry.ClassesRoot.OpenSubKey(@".msm\Shell\Open\Command",false); string value="\"" + Application.StartupPath + "\\MeasureMan.exe\"" + " \"%1\""; if (mainkey == null) { RegistryKey key = Registry.ClassesRoot.CreateSubKey(".msm"); key.SetValue("File Type", "msm File"); key.CreateSubKey(@"Shell\Open\Command").SetValue("",value); SHChangeNotify(HChangeNotifyEventID.SHCNE_ASSOCCHANGED, HChangeNotifyFlags.SHCNF_IDLIST | HChangeNotifyFlags.SHCNF_FLUSH, IntPtr.Zero, IntPtr.Zero); } else if (!value.Equals(mainkey.GetValue("").ToString())) { RegistryKey anotherKey = Registry.ClassesRoot.OpenSubKey(@".msm\Shell\Open\Command", true); anotherKey.SetValue("", value); SHChangeNotify(HChangeNotifyEventID.SHCNE_ASSOCCHANGED, HChangeNotifyFlags.SHCNF_IDLIST | HChangeNotifyFlags.SHCNF_FLUSH, IntPtr.Zero, IntPtr.Zero); } } catch { MessageBox.Show("以管理员身份运行可将工程文件关联到此程序"); }

但在修改完注册表后一定要进行注册表的刷新，对应上面的SHChangeNotify方法，这不是一个.NET自带的方法，而是系统文件shell32.dll中的方法，引用方法的方式如下：

[DllImport("shell32.dll")] static extern void SHChangeNotify(HChangeNotifyEventID wEventId, HChangeNotifyFlags uFlags, IntPtr dwItem1, IntPtr dwItem2);

其中HChangeNotifyEventID和HChangeNotifyFlags都是枚举类型，其定义如下：

enum HChangeNotifyEventID { /// <summary> /// All events have occurred. /// </summary> SHCNE_ALLEVENTS = 0x7FFFFFFF, /// <summary> /// A file type association has changed. <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> /// must be specified in the uFlags parameter. /// dwItem1 and dwItem2 are not used and must be <see langword="null"/>. /// </summary> SHCNE_ASSOCCHANGED = 0x08000000, /// <summary> /// The attributes of an item or folder have changed. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the item or folder that has changed. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_ATTRIBUTES = 0x00000800, /// <summary> /// A nonfolder item has been created. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the item that was created. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_CREATE = 0x00000002, /// <summary> /// A nonfolder item has been deleted. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the item that was deleted. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_DELETE = 0x00000004, /// <summary> /// A drive has been added. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the root of the drive that was added. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_DRIVEADD = 0x00000100, /// <summary> /// A drive has been added and the Shell should create a new window for the drive. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the root of the drive that was added. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_DRIVEADDGUI = 0x00010000, /// <summary> /// A drive has been removed. <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the root of the drive that was removed. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_DRIVEREMOVED = 0x00000080, /// <summary> /// Not currently used. /// </summary> SHCNE_EXTENDED_EVENT = 0x04000000, /// <summary> /// The amount of free space on a drive has changed. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the root of the drive on which the free space changed. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_FREESPACE = 0x00040000, /// <summary> /// Storage media has been inserted into a drive. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the root of the drive that contains the new media. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_MEDIAINSERTED = 0x00000020, /// <summary> /// Storage media has been removed from a drive. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the root of the drive from which the media was removed. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_MEDIAREMOVED = 0x00000040, /// <summary> /// A folder has been created. <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> /// or <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the folder that was created. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_MKDIR = 0x00000008, /// <summary> /// A folder on the local computer is being shared via the network. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the folder that is being shared. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_NETSHARE = 0x00000200, /// <summary> /// A folder on the local computer is no longer being shared via the network. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the folder that is no longer being shared. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_NETUNSHARE = 0x00000400, /// <summary> /// The name of a folder has changed. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the previous pointer to an item identifier list (PIDL) or name of the folder. /// dwItem2 contains the new PIDL or name of the folder. /// </summary> SHCNE_RENAMEFOLDER = 0x00020000, /// <summary> /// The name of a nonfolder item has changed. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the previous PIDL or name of the item. /// dwItem2 contains the new PIDL or name of the item. /// </summary> SHCNE_RENAMEITEM = 0x00000001, /// <summary> /// A folder has been removed. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the folder that was removed. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_RMDIR = 0x00000010, /// <summary> /// The computer has disconnected from a server. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the server from which the computer was disconnected. /// dwItem2 is not used and should be <see langword="null"/>. /// </summary> SHCNE_SERVERDISCONNECT = 0x00004000, /// <summary> /// The contents of an existing folder have changed, /// but the folder still exists and has not been renamed. /// <see cref="HChangeNotifyFlags.SHCNF_IDLIST"/> or /// <see cref="HChangeNotifyFlags.SHCNF_PATH"/> must be specified in uFlags. /// dwItem1 contains the folder that has changed. /// dwItem2 is not used and should be <see langword="null"/>. /// If a folder has been created, deleted, or renamed, use SHCNE_MKDIR, SHCNE_RMDIR, or /// SHCNE_RENAMEFOLDER, respectively, instead. /// </summary> SHCNE_UPDATEDIR = 0x00001000, /// <summary> /// An image in the system image list has changed. /// <see cref="HChangeNotifyFlags.SHCNF_DWORD"/> must be specified in uFlags. /// </summary> SHCNE_UPDATEIMAGE = 0x00008000, } enum HChangeNotifyFlags { /// <summary> /// The dwItem1 and dwItem2 parameters are DWORD values. /// </summary> SHCNF_DWORD = 0x0003, /// <summary> /// dwItem1 and dwItem2 are the addresses of ITEMIDLIST structures that /// represent the item(s) affected by the change. /// Each ITEMIDLIST must be relative to the desktop folder. /// </summary> SHCNF_IDLIST = 0x0000, /// <summary> /// dwItem1 and dwItem2 are the addresses of null-terminated strings of /// maximum length MAX_PATH that contain the full path names /// of the items affected by the change. /// </summary> SHCNF_PATHA = 0x0001, /// <summary> /// dwItem1 and dwItem2 are the addresses of null-terminated strings of /// maximum length MAX_PATH that contain the full path names /// of the items affected by the change. /// </summary> SHCNF_PATHW = 0x0005, /// <summary> /// dwItem1 and dwItem2 are the addresses of null-terminated strings that /// represent the friendly names of the printer(s) affected by the change. /// </summary> SHCNF_PRINTERA = 0x0002, /// <summary> /// dwItem1 and dwItem2 are the addresses of null-terminated strings that /// represent the friendly names of the printer(s) affected by the change. /// </summary> SHCNF_PRINTERW = 0x0006, /// <summary> /// The function should not return until the notification /// has been delivered to all affected components. /// As this flag modifies other data-type flags, it cannot by used by itself. /// </summary> SHCNF_FLUSH = 0x1000, /// <summary> /// The function should begin delivering notifications to all affected components /// but should return as soon as the notification process has begun. /// As this flag modifies other data-type flags, it cannot by used by itself. /// </summary> SHCNF_FLUSHNOWAIT = 0x2000 }

最后，为了能双击打开msm文件，还需要修改Application.Run方法，Environment.GetCommandLineArgs可以获得当前程序运行的参数，至少有1个参数，就是程序所在路径，第二个参数可选，为msm文件路径，在cmd中操作同理。

string[] args = Environment.GetCommandLineArgs(); if (args.Length == 2) Application.Run(new MeasureMan(args[1])); else Application.Run(new MeasureMan(null));

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