A preprocessor for WPF XAML files that enables conditional compilation using XML comments, providing functionality similar to C#'s #if...#endif preprocessor directives.

• Use conditional compilation in XAML files
• Compatible with existing DefineConstants from C# projects
• Integrates with MSBuild process
• Supports both true/false conditions
• Preserves source files (processes intermediate copies)
• Full UTF-8 with BOM support for XAML compatibility

<!-- fix_issue_001:true -->
<Button Content="New Implementation"/>
<!-- end fix_issue_001:true -->

<!-- fix_issue_001:false -->
<Button Content="Old Implementation"/>
<!-- end fix_issue_001:false -->

Install via NuGet Package Manager:

Install-Package XamlPreprocessor

Define your constants through:

1. MSBuild command line:

msbuild.exe /p:DefineConstants="fix_issue_001;feature_002"

2. Or project file (.csproj):

<PropertyGroup>
  <DefineConstants>$(DefineConstants);fix_issue_001;feature_002</DefineConstants>
</PropertyGroup>

1. During build, creates preprocessed copies of XAML files in the intermediate directory
2. Applies XSLT transformation based on defined constants
3. Uses preprocessed copies for compilation while preserving source files
4. Handles proper UTF-8 encoding with BOM for XAML compatibility

Contributions are welcome! Please feel free to submit a Pull Request.

This project is licensed under the MIT License