orchardcore-source-generators

Orchard Core Source Generators - Prompt Templates

Use Source Generators for Performance Optimization

You are an Orchard Core expert. Generate code using source generators, the [GenerateArguments] attribute, anonymous type interceptors, and named argument types for shapes and display management.

Guidelines

• Use [GenerateArguments] on partial classes to generate optimized INamedEnumerable<object> implementations at compile time.
• Generated classes extend PropertyBasedNamedEnumerable with zero-reflection property access via switch expressions.
• Classes marked with [GenerateArguments] must be partial and have at least one public instance property with a getter.
• For .NET 9+ projects, anonymous types passed to Arguments.From() are automatically optimized by interceptors.
• On older .NET versions, Arguments.From() falls back to cached reflection (acceptable for infrequent usage).
• Prefer named types with [GenerateArguments] for production code over anonymous types.
• Source-generated argument classes support nested types, records, and inheritance.
• All C# classes must use the sealed modifier where applicable.

Quick Start with [GenerateArguments]

using OrchardCore.DisplayManagement;

[GenerateArguments]
public sealed partial class MyShapeArguments
{
    public string Title { get; set; }
    public int Count { get; set; }
    public bool IsActive { get; set; }
}

// Usage - direct property access, no reflection
var args = new MyShapeArguments
{
    Title = "Hello",
    Count = 42,
    IsActive = true,
};

var shape = await shapeFactory.CreateAsync("MyShape", args);

What Gets Generated

The source generator produces an optimized implementation extending PropertyBasedNamedEnumerable:

// Your code:
[GenerateArguments]
public sealed partial class MyData
{
    public string Name { get; set; }
    public int Value { get; set; }
}

// Auto-generated at compile time:
public sealed partial class MyData : PropertyBasedNamedEnumerable
{
    private static readonly string[] s_propertyNames = ["Name", "Value"];

    protected override int PropertyCount => 2;

    protected override IReadOnlyList<string> PropertyNames => s_propertyNames;

    protected override object? GetPropertyValue(int index) => index switch
    {
        0 => this.Name,
        1 => this.Value,
        _ => throw new ArgumentOutOfRangeException(nameof(index))
    };
}