filtered file path list treeview in wpf

Question

I works in c# and have a class that fills a TreeView in Wpf, my problems is that i can't filter del path depending on the elements, I enter a textbox

This is how it currently works for me

And this is how I need it to come out when entering the value in the textbox

public class ItemProvider
{
    public List GetItems(string path)
    {
        var items = new List();
        var dirInfo = new DirectoryInfo(path);

        foreach (var directory in dirInfo.GetDirectories())
        {
            var item = new DirectoryItem
            {
                Name = directory.Name,
                Path = directory.FullName,
                Items = GetItems(directory.FullName)
            };

            items.Add(item);
        }

        foreach (var file in dirInfo.GetFiles())
        {
            var item = new FileItem
            {
                Name = file.Name,
                Path = file.FullName
            };

            items.Add(item);
        }

        return items;
    }
}

Andrew KeepCoding · Answer

This is how I'd implement this. (Actually, implemented for this answer.)

I'm using the CommunityToolkit.Mvvm NuGet package to implement the MVVM design.

ItemProvider.cs

using System.Collections.Generic;

namespace WpfAppTreeViewTest;

public class Item
{
    public string Name { get; set; }
    public string Path { get; set; }
}

public class FileItem : Item
{
}

public class DirectoryItem : Item
{
    public List Items { get; set; }

    public DirectoryItem()
    {
        Items = new List();
    }
}

public class ItemProvider
{
    public List GetItems(string path)
    {
        return new List()
        {
            new DirectoryItem()
            {
                Name = "comedy",
                Items = new List()
                {
                    new FileItem() { Name = "1001.PDF" },
                    new FileItem() { Name = "1002.PDF" },
                    new FileItem() { Name = "1003.PDF" },
                },
            },
            new DirectoryItem()
            {
                Name = "horror",
                Items = new List()
                {
                    new FileItem() { Name = "1005.PDF" },
                    new FileItem() { Name = "1006.PDF" },
                },
            },
            new DirectoryItem()
            {
                Name = "suspense",
                Items = new List()
                {
                    new FileItem() { Name = "1002.PDF" },
                    new FileItem() { Name = "1005.PDF" },
                    new FileItem() { Name = "1006.PDF" },
                },
            },
        };
    }
}

MainWindowViewModel.cs

using CommunityToolkit.Mvvm.ComponentModel;
using System.Collections.Generic;
using System.Linq;

namespace WpfAppTreeViewTest;
// This class needs to be partial for the CommunityToolkit's source generators.
public partial class MainWindowViewModel : ObservableObject
{
    // The source generators will auto-create a "FilterText" property.
    [ObservableProperty]
    private string filterText = string.Empty;

    // The source generators will auto-create a "FilteredItems" property.
    [ObservableProperty]
    private IEnumerable? filteredItems;

    private List? items;

    public MainWindowViewModel()
    {
        var itemProvider = new ItemProvider();
        this.items = itemProvider.GetItems("");
        FilteredItems = this.items;
    }

    // This is a "partial" method created by the source generator.
    // This method will be called everytime "FilterText" changes.
    partial void OnFilterTextChanged(string value)
    {
        FilteredItems = this.items?
            .OfType()
            .Select(d => new DirectoryItem()
            {
                Name = d.Name,
                Path = d.Path,
                Items = d.Items.Where(x => x.Name.Contains(value)).ToList(),
            })
            .Where(x => x.Items.Any() is true);
    }
}

MainWindow.cs

using System.Windows;
using System.Windows.Controls;

namespace WpfAppTreeViewTest;

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    public MainWindowViewModel ViewModel { get; } = new();
}

MainWindow.xaml

filtered file path list treeview in wpf

1 Answers