LNKLib 1.0.1

LNKLib

A zero-dependency .NET library for creating Windows Shell Link (.lnk) shortcut files in memory.

Features

• Create shortcuts to local files, folders, network shares, and printers
• Environment variable support (e.g. %windir%\notepad.exe)
• Custom icon, arguments, working directory, and description
• Window style control (normal, maximized, minimized)
• Run as Administrator support
• Hotkey assignment (key + modifier combinations)
• Argument padding to hide command-line arguments in shortcut properties
• Returns raw byte[] — no COM interop or Windows Shell dependency
• Targets .NET 10

Installation

Add a reference to the LNKLib project or install the NuGet package:

dotnet add package LNKLib

Usage

using LNKLib;

// Simple file shortcut
byte[] lnk = Shortcut.Create(@"C:\Windows\notepad.exe");
File.WriteAllBytes("Notepad.lnk", lnk);

// Shortcut with all options
byte[] lnk = Shortcut.Create(
    target: @"C:\Windows\notepad.exe",
    arguments: @"C:\notes.txt",
    iconLocation: @"C:\Windows\notepad.exe",
    iconIndex: 0,
    description: "My Notepad Shortcut",
    workingDirectory: @"C:\Windows",
    windowStyle: ShortcutWindowStyle.Normal);
File.WriteAllBytes("Notepad.lnk", lnk);

// Network share shortcut
byte[] lnk = Shortcut.Create(@"\\server\share\document.docx");

// Environment variable shortcut
byte[] lnk = Shortcut.Create(@"%windir%\notepad.exe");

// Run as Administrator
byte[] lnk = Shortcut.Create(
    target: @"C:\Windows\System32\cmd.exe",
    runAsAdmin: true);

// Maximized window with hotkey (Ctrl+Alt+T)
byte[] lnk = Shortcut.Create(
    target: @"C:\Windows\notepad.exe",
    windowStyle: ShortcutWindowStyle.Maximized,
    hotkeyKey: 0x54,  // 'T' virtual key code
    hotkeyModifiers: HotkeyModifiers.Control | HotkeyModifiers.Alt);

// Shortcut with padded arguments (hidden in properties UI)
byte[] lnk = Shortcut.Create(
    target: @"C:\Windows\notepad.exe",
    arguments: "--secret-flag",
    padArguments: true);

API

public static byte[] Shortcut.Create(
    string target,                                          // Target path (required)
    string? arguments = null,                               // Command-line arguments
    bool padArguments = false,                              // Pad arguments to 31 KB buffer
    string? iconLocation = null,                            // Icon file path
    int iconIndex = 0,                                      // Icon index within file
    string? description = null,                             // Shortcut description
    string? workingDirectory = null,                         // Working directory
    bool isPrinterLink = false,                             // Treat target as a printer
    ShortcutWindowStyle windowStyle = Normal,               // Initial window state
    bool runAsAdmin = false,                                // Run target as administrator
    byte hotkeyKey = 0,                                     // Virtual key code (0 = none)
    HotkeyModifiers hotkeyModifiers = None)                 // Hotkey modifier keys

ShortcutWindowStyle

HotkeyModifiers

Combinable flags for hotkey modifier keys:

The hotkeyKey parameter accepts a virtual key code. Common values: 0x41–0x5A for A–Z, 0x70–0x87 for F1–F24.

Argument Padding

When padArguments is true, the arguments string is placed at the end of a 31 KB buffer filled with whitespace and control characters (CR, Tab, LF, file/group/record/unit separators, Space). This pushes the actual arguments beyond what the Windows shortcut properties dialog displays, effectively hiding them from casual inspection.

File vs. Directory Detection

The library classifies the target as a file or directory based on its extension length:

• File (FILE_ATTRIBUTE_ARCHIVE): Extension is 1–3 characters (e.g. .exe, .txt, .a)
• Directory (FILE_ATTRIBUTE_DIRECTORY): No extension, or extension longer than 3 characters

Path Handling

• Local paths are split on the first \. The root portion gets a trailing \ (e.g. C:\), the remainder becomes the leaf item.
• Network paths (starting with \\) are split on the last \. The server+share portion is the root, the final component is the leaf.
• Printer links treat the entire target as the root (no leaf item).

Building

dotnet build

Testing

dotnet test

License

MIT