设置IsFolderPicker=true时，CommonOpenFileDialog能否同时显示文件？

Hey there! Let's break this down clearly for you:

Short answer: No, you can't make CommonOpenFileDialog display files while IsFolderPicker = true. Here's why, plus practical workarounds:

Why It's Not Possible #

The IsFolderPicker property is purpose-built to switch the dialog into a pure folder-selection mode. Under the hood, it leverages Windows' native IFileOpenDialog interface, and setting this flag tells the system to completely hide file entries from the dialog's view. This is a deliberate design choice—there’s no built-in way to override this behavior while keeping the folder picker active.

Workarounds to Select Both Files and Folders #

If you need users to choose either files or folders, here are two reliable approaches:

1. Use the Regular File Dialog (Disable IsFolderPicker) #

Turn off IsFolderPicker, let users select both files and folders, then handle the results to distinguish between them. This is the simplest solution:

var dlg = new CommonOpenFileDialog();
dlg.Title = "Select files or directories";
dlg.Multiselect = true; // Optional: let users pick multiple items at once
dlg.Filters.Add(new CommonFileDialogFilter("All Items", "*.*")); // Show all files and folders

if (dlg.ShowDialog() == CommonFileDialogResult.Ok)
{
    foreach (var selectedPath in dlg.FileNames)
    {
        if (Directory.Exists(selectedPath))
        {
            // Handle the selected folder
            Console.WriteLine($"Selected folder: {selectedPath}");
        }
        else if (File.Exists(selectedPath))
        {
            // Handle the selected file
            Console.WriteLine($"Selected file: {selectedPath}");
        }
    }
}

When IsFolderPicker is false, users can select folders just like files—you just need to check each selected path to determine its type.

2. Build a Custom Dialog (Advanced) #

If you need full control over the UI (e.g., custom styling for files vs. folders), you could create a custom WPF/WinForms dialog that manually scans directories and displays both file and folder entries. This requires more work but gives you complete flexibility over the user experience.

Final Note #

The folder picker mode of CommonOpenFileDialog is intentionally restricted to only show directories, so there’s no "hack" to force files to appear there. The regular dialog approach is your best bet for supporting both file and folder selections.

内容的提问来源于stack exchange，提问作者Camadas