ChmViewer

ChmViewer is a Windows WPF application for viewing the contents of a .chm help file. It also provides basic search/navigation capabilities inside the CHM.

This repository contains both the application (app/) and the supporting CHM reading/viewing libraries (lib/).

Solution structure

Solution file: ChmViewer.sln

Projects:

• app/ChmViewer (WPF Application)

  • Target: net10.0-windows
    • Hosts the CefSharp-based WPF control HtmlHelp.Wpf.Controls.ChmViewerControl.
    • Supports opening a CHM file using the built-in toolbar Open button.
    • Supports opening a CHM file via command-line argument (pass a .chm file path).
    • Toolbar and status bar visibility can be controlled via ChmViewerViewModel.ShowToolbar and ChmViewerViewModel.ShowStatusBar.

• app/ChmViewerTest (WPF Application)

  • Target: net10.0-windows
  • Demonstrates additional/legacy flows (library-based searching, optional CHM decompile + file search).
  • Includes sample documents under app/ChmViewerTest/Documents/.

• lib/HtmlHelp (Core CHM reader library)

  • Target: net10.0
  • Opens CHM content, reads index/TOC, and performs searches.

• lib/HtmlHelp.Wpf (WPF integration)

  • Target: net10.0-windows
    • Provides HtmlHelp.Wpf.Controls.ChmViewerControl and HtmlHelp.Wpf.Controls.ChmViewerViewModel for embedding a CHM viewer in any WPF window.

• lib/HtmlHelp.WinForms (WinForms integration)

  • Target: net10.0-windows

Viewer options in this repository

Embedded CefSharp viewer (recommended)

The main viewer experience is implemented by HtmlHelp.Wpf.Controls.ChmViewerControl:

• TOC on the left
• CefSharp Chromium browser on the right
• Optional toolbar (Back/Forward/Reload/Open)
• Optional status bar

The control is driven by HtmlHelp.Wpf.Controls.ChmViewerViewModel.

Legacy/demo flows (in app/ChmViewerTest)

app/ChmViewerTest contains additional flows used for testing/demonstration, including:

• In-CHM keyword search using lib/HtmlHelp.
• Optional decompile-to-HTML flow using Windows hh.exe.

Notes:

• The hh.exe approach only works on Windows.
• You need write permissions to the target folder.

Dependencies (NuGet packages)

Packages used per project:

app/ChmViewer

• HtmlAgilityPack (1.11.24) – HTML parsing/processing.
• CefSharp.Wpf.NETCore (144.0.120) – Chromium-based WPF browser control.

lib/HtmlHelp

• SharpZipLib (1.4.2) – used for some content/stream operations.
• System.Resources.Extensions (10.0.2) – resource support.

lib/HtmlHelp.Wpf

• CefSharp.Wpf.NETCore (144.0.120)
• chromiumembeddedframework.runtime.win-x64 (144.0.12)
• chromiumembeddedframework.runtime.win-x86 (144.0.12)

Setup and build requirements

Operating system

• Windows (required by WPF and hh.exe)

Visual Studio

The ChmViewer.sln header shows Visual Studio Version 18, so:

• You need a Visual Studio version that supports .NET 10 (often Preview).
• Ensure the .NET Desktop Development workload is installed.

.NET SDK

• app/ChmViewer, lib/HtmlHelp.Wpf, lib/HtmlHelp.WinForms: net10.0-windows
• lib/HtmlHelp: net10.0

You need the .NET 10 SDK installed (may be Preview).

Run with Visual Studio

1. Open ChmViewer.sln.
2. Set ChmViewer as the startup project.
3. Choose x64 (recommended) or x86.
4. Press F5.
5. Select a .chm file using the toolbar Open button.

If you want to run the demo/test flows instead, set ChmViewerTest as the startup project.

Build from the command line

From the repository root:

• dotnet restore
• dotnet build ChmViewer.sln -c Release

Helper scripts

• delete-bin-obj-folders.bat: Removes bin/ and obj/ folders across all projects.

Common issues

• CefSharp dependencies missing / not working: Ensure the selected platform (x64/x86) matches the runtime packages.
• CefSharp cache locked: Startup can fail if another process is already using the same cache directory (under LocalAppData).
• WPF WebBrowser behavior: The WebBrowser control depends on Windows/IE components; rendering behavior can vary by machine configuration.

Publishing notes

app/ChmViewer/ChmViewer.csproj contains settings for single-file publish. When publishing with PublishSingleFile=true, the project is configured to use a dedicated StartupObject for CefSharp.