DNS Changer

A Windows desktop application for managing DNS servers across your network adapters. Built with a high-performance C++20 core and a modern C# WPF interface.

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Architecture

Layer 1 — Native engine (C++)

Component	Description
DLL	dns_core.dll
API	WinAPI with netsh fallback for DNS management
Interop	C API for C# via P/Invoke; all data as JSON
Logs	C:\ProgramData\DnsChanger\dns_core.log

Layer 2 — Desktop UI (C# .NET 8)

Component	Description
Executable	DNSChanger.exe
Stack	WPF, MVVM
Theme	Dark by default; modern typography and layout
Extras	System tray icon, background mode

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Features

• Network discovery — Detects adapters (Wi‑Fi, Ethernet, VPN, virtual)
• DNS catalog — 30+ providers (Google, Cloudflare, Quad9, OpenDNS, AdGuard, etc.)
• Custom DNS — Add and manage your own servers
• Speed test — Real DNS queries with latency, packet loss, and stability
• One-click apply — Set DNS per adapter
• Restore default — Revert to DHCP DNS
• System tray — Quick actions and background operation

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Requirements

Layer	Requirements
C++ DLL	CMake 3.20+, Visual Studio 2022 (or MSVC), Windows SDK 10.0+
WPF app	.NET 8 SDK, Visual Studio 2022 or VS Code with C#

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Build

1. Build the C++ DLL

cd cpp_core
mkdir build -ErrorAction SilentlyContinue
cd build
cmake .. -G "Visual Studio 17 2022" -A x64
cmake --build . --config Release

Output: build\bin\Release\dns_core.dll (or build\Release\dns_core.dll).

2. Copy DLL into the WPF project

From cpp_core\build:

copy bin\Release\dns_core.dll ..\..\windows_gui\
# or, if different layout:
copy Release\dns_core.dll ..\..\windows_gui\

3. Build and run the WPF app

cd ..\..\windows_gui
dotnet restore
dotnet build --configuration Release
dotnet run --configuration Release

One-command build

From the repository root:

.\build.ps1

This builds the C++ DLL, copies it to windows_gui, and builds the WPF application.

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Release installer

Download (recommended)

1. Open Releases.
2. Download the latest DNSChanger-Setup-x.x.x.exe.
3. Run the installer (UAC may prompt).
4. Launch DNS Changer from the Start menu or desktop. Use Run as administrator when changing DNS.