首页 / 知识

关于.net：在C#中浏览目录

2023-04-12 06:04:00

Browse for a directory in C#

如何向用户显示允许他/她选择目录的控件？

似乎没有任何本机.net控件可以执行此操作？

1
2
3
4
5

string folderPath ="";
FolderBrowserDialog folderBrowserDialog1 = new FolderBrowserDialog();
if (folderBrowserDialog1.ShowDialog() == DialogResult.OK) {
folderPath = folderBrowserDialog1.SelectedPath ;
}

FolderBrowserDialog类是最佳选择。

_{注意：不能保证此代码在.Net框架的将来版本中将起作用。总体上来说，使用私有的.Net框架内部结构(通过反射)可能并不理想。使用底部提到的互操作解决方案，因为Windows API更改的可能性较小。}

如果您要查找的文件夹选择器看起来更像Windows 7对话框，并且能够从底部的文本框和左侧的导航窗格(具有收藏夹和常用位置)进行复制和粘贴，则可以以非常轻巧的方式访问它。

FolderBrowserDialog用户界面非常小：

enter

using System;
using System.Reflection;
using System.Windows.Forms;

namespace MyCoolCompany.Shuriken {
/// <summary>
/// Present the Windows Vista-style open file dialog to select a folder. Fall back for older Windows Versions
/// </summary>
public class FolderSelectDialog {
private string _initialDirectory;
private string _title;
private string _fileName ="";

public string InitialDirectory {
get { return string.IsNullOrEmpty(_initialDirectory) ? Environment.CurrentDirectory : _initialDirectory; }
set { _initialDirectory = value; }
}
public string Title {
get { return _title ??"Select a folder"; }
set { _title = value; }
}
public string FileName { get { return _fileName; } }

public bool Show() { return Show(IntPtr.Zero); }

/// <param name="hWndOwner">Handle of the control or window to be the parent of the file dialog</param>
/// <returns>true if the user clicks OK</returns>
public bool Show(IntPtr hWndOwner) {
var result = Environment.OSVersion.Version.Major >= 6
? VistaDialog.Show(hWndOwner, InitialDirectory, Title)
: ShowXpDialog(hWndOwner, InitialDirectory, Title);
_fileName = result.FileName;
return result.Result;
}

private struct ShowDialogResult {
public bool Result { get; set; }
public string FileName { get; set; }
}

private static ShowDialogResult ShowXpDialog(IntPtr ownerHandle, string initialDirectory, string title) {
var folderBrowserDialog = new FolderBrowserDialog {
Description = title,
SelectedPath = initialDirectory,
ShowNewFolderButton = false
};
var dialogResult = new ShowDialogResult();
if (folderBrowserDialog.ShowDialog(new WindowWrapper(ownerHandle)) == DialogResult.OK) {
dialogResult.Result = true;
dialogResult.FileName = folderBrowserDialog.SelectedPath;
}
return dialogResult;
}

private static class VistaDialog {
private const string c_foldersFilter ="Folders|\
";

private const BindingFlags c_flags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic;
private readonly static Assembly s_windowsFormsAssembly = typeof(FileDialog).Assembly;
private readonly static Type s_iFileDialogType = s_windowsFormsAssembly.GetType("System.Windows.Forms.FileDialogNative+IFileDialog");
private readonly static MethodInfo s_createVistaDialogMethodInfo = typeof(OpenFileDialog).GetMethod("CreateVistaDialog", c_flags);
private readonly static MethodInfo s_onBeforeVistaDialogMethodInfo = typeof(OpenFileDialog).GetMethod("OnBeforeVistaDialog", c_flags);
private readonly static MethodInfo s_getOptionsMethodInfo = typeof(FileDialog).GetMethod("GetOptions", c_flags);
private readonly static MethodInfo s_setOptionsMethodInfo = s_iFileDialogType.GetMethod("SetOptions", c_flags);
private readonly static uint s_fosPickFoldersBitFlag = (uint) s_windowsFormsAssembly
.GetType("System.Windows.Forms.FileDialogNative+FOS")
.GetField("FOS_PICKFOLDERS")
.GetValue(null);
private readonly static ConstructorInfo s_vistaDialogEventsConstructorInfo = s_windowsFormsAssembly
.GetType("System.Windows.Forms.FileDialog+VistaDialogEvents")
.GetConstructor(c_flags, null, new[] { typeof(FileDialog) }, null);
private readonly static MethodInfo s_adviseMethodInfo = s_iFileDialogType.GetMethod("Advise");
private readonly static MethodInfo s_unAdviseMethodInfo = s_iFileDialogType.GetMethod("Unadvise");
private readonly static MethodInfo s_showMethodInfo = s_iFileDialogType.GetMethod("Show");

public static ShowDialogResult Show(IntPtr ownerHandle, string initialDirectory, string title) {
var openFileDialog = new OpenFileDialog {
AddExtension = false,
CheckFileExists = false,
DereferenceLinks = true,
Filter = c_foldersFilter,
InitialDirectory = initialDirectory,
Multiselect = false,
Title = title
};

var iFileDialog = s_createVistaDialogMethodInfo.Invoke(openFileDialog, new object[] { });
s_onBeforeVistaDialogMethodInfo.Invoke(openFileDialog, new[] { iFileDialog });
s_setOptionsMethodInfo.Invoke(iFileDialog, new object[] { (uint) s_getOptionsMethodInfo.Invoke(openFileDialog, new object[] { }) | s_fosPickFoldersBitFlag });
var adviseParametersWithOutputConnectionToken = new[] { s_vistaDialogEventsConstructorInfo.Invoke(new object[] { openFileDialog }), 0U };
s_adviseMethodInfo.Invoke(iFileDialog, adviseParametersWithOutputConnectionToken);

try {
int retVal = (int) s_showMethodInfo.Invoke(iFileDialog, new object[] { ownerHandle });
return new ShowDialogResult {
Result = retVal == 0,
FileName = openFileDialog.FileName
};
}
finally {
s_unAdviseMethodInfo.Invoke(iFileDialog, new[] { adviseParametersWithOutputConnectionToken[1] });
}
}
}

// Wrap an IWin32Window around an IntPtr
private class WindowWrapper : IWin32Window {
private readonly IntPtr _handle;
public WindowWrapper(IntPtr handle) { _handle = handle; }
public IntPtr Handle { get { return _handle; } }
}
}
}

我将其开发为lyquidity.com的Bill Seddon(我没有隶属关系)的.NET Win 7样式文件夹选择对话框的清理版本。我写自己的书是因为他的解决方案需要一个额外的Reflection类，而该类不需要为此专门的目的而使用，它使用基于异常的流控制，并且不缓存其反射调用的结果。请注意，嵌套的静态VistaDialog类是这样的，因此如果从未调用Show方法，则不会尝试填充其静态反射变量。

它在Windows窗体中的用法如下：

1
2
3
4
5
6
7

var dialog = new FolderSelectDialog {
InitialDirectory = musicFolderTextBox.Text,
Title ="Select a folder to import music from"
};
if (dialog.Show(Handle)) {
musicFolderTextBox.Text = dialog.FileName;
}

您当然可以使用它的选项以及它公开的属性。例如，它允许在Vista风格的对话框中进行多项选择。

此外，请注意，Simon Mourier给出了一个答案，该答案显示了如何直接针对Windows API使用互操作来完成完全相同的工作，但是如果使用的是旧版本的Windows，则必须对他的版本进行补充才能使用较旧的样式对话框视窗。不幸的是，当我制定解决方案时，我还没有找到他的职位。命名您的毒药！

您可以只使用System.Windows.Forms名称空间中的FolderBrowserDialog类。

请不要尝试使用TreeView / DirectoryInfo类自行滚动。一方面，使用SHBrowseForFolder可以免费获得许多不错的功能(图标/右键单击/网络)。对于另外一些情况，您可能不会意识到。

甚至更好的是，您可以将此代码放在类文件中

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223

using System;
using System.IO;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Windows.Forms;

internal class OpenFolderDialog : IDisposable {

/// <summary>
/// Gets/sets folder in which dialog will be open.
/// </summary>
public string InitialFolder { get; set; }

/// <summary>
/// Gets/sets directory in which dialog will be open if there is no recent directory available.
/// </summary>
public string DefaultFolder { get; set; }

/// <summary>
/// Gets selected folder.
/// </summary>
public string Folder { get; private set; }

internal DialogResult ShowDialog(IWin32Window owner) {
if (Environment.OSVersion.Version.Major >= 6) {
return ShowVistaDialog(owner);
} else {
return ShowLegacyDialog(owner);
}
}

private DialogResult ShowVistaDialog(IWin32Window owner) {
var frm = (NativeMethods.IFileDialog)(new NativeMethods.FileOpenDialogRCW());
uint options;
frm.GetOptions(out options);
options |= NativeMethods.FOS_PICKFOLDERS | NativeMethods.FOS_FORCEFILESYSTEM | NativeMethods.FOS_NOVALIDATE | NativeMethods.FOS_NOTESTFILECREATE | NativeMethods.FOS_DONTADDTORECENT;
frm.SetOptions(options);
if (this.InitialFolder != null) {
NativeMethods.IShellItem directoryShellItem;
var riid = new Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"); //IShellItem
if (NativeMethods.SHCreateItemFromParsingName(this.InitialFolder, IntPtr.Zero, ref riid, out directoryShellItem) == NativeMethods.S_OK) {
frm.SetFolder(directoryShellItem);
}
}
if (this.DefaultFolder != null) {
NativeMethods.IShellItem directoryShellItem;
var riid = new Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"); //IShellItem
if (NativeMethods.SHCreateItemFromParsingName(this.DefaultFolder, IntPtr.Zero, ref riid, out directoryShellItem) == NativeMethods.S_OK) {
frm.SetDefaultFolder(directoryShellItem);
}
}

if (frm.Show(owner.Handle) == NativeMethods.S_OK) {
NativeMethods.IShellItem shellItem;
if (frm.GetResult(out shellItem) == NativeMethods.S_OK) {
IntPtr pszString;
if (shellItem.GetDisplayName(NativeMethods.SIGDN_FILESYSPATH, out pszString) == NativeMethods.S_OK) {
if (pszString != IntPtr.Zero) {
try {
this.Folder = Marshal.PtrToStringAuto(pszString);
return DialogResult.OK;
} finally {
Marshal.FreeCoTaskMem(pszString);
}
}
}
}
}
return DialogResult.Cancel;
}

private DialogResult ShowLegacyDialog(IWin32Window owner) {
using (var frm = new SaveFileDialog()) {
frm.CheckFileExists = false;
frm.CheckPathExists = true;
frm.CreatePrompt = false;
frm.Filter ="|" + Guid.Empty.ToString();
frm.FileName ="any";
if (this.InitialFolder != null) { frm.InitialDirectory = this.InitialFolder; }
frm.OverwritePrompt = false;
frm.Title ="Select Folder";
frm.ValidateNames = false;
if (frm.ShowDialog(owner) == DialogResult.OK) {
this.Folder = Path.GetDirectoryName(frm.FileName);
return DialogResult.OK;
} else {
return DialogResult.Cancel;
}
}
}

public void Dispose() { } //just to have possibility of Using statement.

}

internal static class NativeMethods {

#region Constants

public const uint FOS_PICKFOLDERS = 0x00000020;
public const uint FOS_FORCEFILESYSTEM = 0x00000040;
public const uint FOS_NOVALIDATE = 0x00000100;
public const uint FOS_NOTESTFILECREATE = 0x00010000;
public const uint FOS_DONTADDTORECENT = 0x02000000;

public const uint S_OK = 0x0000;

public const uint SIGDN_FILESYSPATH = 0x80058000;

#endregion

#region COM

[ComImport, ClassInterface(ClassInterfaceType.None), TypeLibType(TypeLibTypeFlags.FCanCreate), Guid("DC1C5A9C-E88A-4DDE-A5A1-60F82A20AEF7")]
internal class FileOpenDialogRCW { }

[ComImport(), Guid("42F85136-DB7E-439C-85F1-E4075D135FC8"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface IFileDialog {
[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
[PreserveSig()]
uint Show([In, Optional] IntPtr hwndOwner); //IModalWindow

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetFileTypes([In] uint cFileTypes, [In, MarshalAs(UnmanagedType.LPArray)] IntPtr rgFilterSpec);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetFileTypeIndex([In] uint iFileType);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetFileTypeIndex(out uint piFileType);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint Advise([In, MarshalAs(UnmanagedType.Interface)] IntPtr pfde, out uint pdwCookie);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint Unadvise([In] uint dwCookie);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetOptions([In] uint fos);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetOptions(out uint fos);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
void SetDefaultFolder([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetFolder([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetFolder([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetCurrentSelection([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetFileName([In, MarshalAs(UnmanagedType.LPWStr)] string pszName);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetFileName([MarshalAs(UnmanagedType.LPWStr)] out string pszName);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetTitle([In, MarshalAs(UnmanagedType.LPWStr)] string pszTitle);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetOkButtonLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszText);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetFileNameLabel([In, MarshalAs(UnmanagedType.LPWStr)] string pszLabel);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetResult([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint AddPlace([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi, uint fdap);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetDefaultExtension([In, MarshalAs(UnmanagedType.LPWStr)] string pszDefaultExtension);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint Close([MarshalAs(UnmanagedType.Error)] uint hr);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetClientGuid([In] ref Guid guid);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint ClearClientData();

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint SetFilter([MarshalAs(UnmanagedType.Interface)] IntPtr pFilter);
}

[ComImport, Guid("43826D1E-E718-42EE-BC55-A1E261C37BFE"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface IShellItem {
[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint BindToHandler([In] IntPtr pbc, [In] ref Guid rbhid, [In] ref Guid riid, [Out, MarshalAs(UnmanagedType.Interface)] out IntPtr ppvOut);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetParent([MarshalAs(UnmanagedType.Interface)] out IShellItem ppsi);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetDisplayName([In] uint sigdnName, out IntPtr ppszName);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint GetAttributes([In] uint sfgaoMask, out uint psfgaoAttribs);

[MethodImpl(MethodImplOptions.InternalCall, MethodCodeType = MethodCodeType.Runtime)]
uint Compare([In, MarshalAs(UnmanagedType.Interface)] IShellItem psi, [In] uint hint, out int piOrder);
}

#endregion

[DllImport("shell32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
internal static extern int SHCreateItemFromParsingName([MarshalAs(UnmanagedType.LPWStr)] string pszPath, IntPtr pbc, ref Guid riid, [MarshalAs(UnmanagedType.Interface)] out IShellItem ppv);

}

并像这样使用它

1
2
3
4
5