在VS . net中,当你为项目选择文件夹时,会显示一个类似于OpenFileDialog或SaveFileDialog的对话框,但设置为只接受文件夹。自从我看到这个,我就想知道它是怎么做到的。我知道FolderBrowserDialog,但我从来都不喜欢那个对话框。它开始太小,不让我利用能够键入路径的优势。

到目前为止,我几乎可以肯定在。net中没有办法做到这一点,但我很好奇在非托管代码中如何做到这一点。如果不从头开始完全重新实现对话框,如何修改对话框以使其具有这种行为呢?

我还想重申,我知道FolderBrowserDialog,但有时我不喜欢使用它,除了真正好奇如何以这种方式配置对话框。告诉我只使用FolderBrowserDialog可以帮助我保持一致的UI体验,但不能满足我的好奇心,所以它不能算作答案。

It's not a Vista-specific thing either; I've been seeing this dialog since VS .NET 2003, so it is doable in Win2k and WinXP. This is less of a "I want to know the proper way to do this" question and more of a "I have been curious about this since I first wanted to do it in VS 2003" question. I understand that Vista's file dialog has an option to do this, but it's been working in XP so I know they did something to get it to work. Vista-specific answers are not answers, because Vista doesn't exist in the question context.

更新:我接受Scott Wisniewski的答案,因为它附带了一个工作示例,但我认为Serge值得赞扬,因为他指出了对话框定制(这在。net中确实很讨厌,但它确实有效),Mark Ransom指出微软可能为这个任务推出了一个自定义对话框。


当前回答

我写了一个名为OpenFileOrFolder的对话框,它允许你打开文件夹或文件。

如果将其AcceptFiles值设置为false,则它只在接受文件夹模式下操作。

你可以在这里从GitHub下载源代码

其他回答

Ookii。对话框包包含一个托管包装器围绕新的(vista风格)文件夹浏览器对话框。它在旧的操作系统上也会优雅地退化。

面向。net 4.5的WPF Ookii对话框,在NuGet上可用 面向。net 4.5的Windows窗体Ookii对话框,可在NuGet上使用

我知道这个问题是关于OpenFileDialog的配置,但看到谷歌把我带到这里,我不妨指出,如果你只是在寻找文件夹,你应该使用FolderBrowserDialog,而不是下面另一个SO问题的答案

如何指定路径使用打开文件对话框在vb.net?

WPF库的Ookii对话框有一个类,它提供了WPF文件夹浏览器对话框的实现。

https://github.com/augustoproiete/ookii-dialogs-wpf

还有一个版本可以使用Windows窗体。

我猜你用的是Vista的VS2008?在这种情况下,我认为FOS_PICKFOLDERS选项在调用Vista文件对话框IFileDialog时被使用。我担心在。net代码中,这将涉及大量粗糙的P/Invoke互操作代码。

第一个解决方案

I developed this as a cleaned up version of .NET Win 7-style folder select dialog by Bill Seddon of lyquidity.com (I have no affiliation). (I learned of his code from another answer on this page). I wrote my own because his solution requires an additional Reflection class that isn't needed for this focused purpose, uses exception-based flow control, doesn't cache the results of its reflection calls. Note that the nested static VistaDialog class is so that its static reflection variables don't try to get populated if the Show method is never called. It falls back to the pre-Vista dialog if not in a high enough Windows version. Should work in Windows 7, 8, 9, 10 and higher (theoretically).

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

namespace ErikE.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|\n";

            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; } }
        }
    }
}

在Windows窗体中是这样使用的:

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

当然,您可以摆弄它的选项以及它所暴露的属性。例如,它允许在vista风格的对话框中进行多选。

第二个解决方案

Simon Mourier给出了一个答案,展示了如何直接使用互操作对Windows API完成完全相同的工作,尽管如果在旧版本的Windows中,他的版本必须补充使用旧样式的对话框。不幸的是,当我制定解决方案时,我还没有找到他的帖子。说出你的毒药!