godot-csharp

Godot C# / .NET (4.x)

Write Godot game code in C#: node subclasses, the engine lifecycle, exports, signals as events, and GDScript interop. Targets Godot 4.7 (.NET / C#) and .NET 8.

When to use

• Use when scripting a Godot game in C# (.cs + .csproj), translating GDScript idioms to C#, exposing [Export] fields, or wiring [Signal] delegates and GetNode.

When not to use: GDScript-specific syntax → godot-gdscript; engine concepts that are language-neutral (scenes, physics, animation) → the relevant godot-* skill. You need the Godot .NET build + the .NET SDK installed; the standard build can't run C#.

Core workflow

1. Use the Godot .NET editor build and install the matching .NET 8 SDK. Creating the first C# script generates a .csproj/.sln. Build with the editor or dotnet build.
2. Every node script is a partial class extending a Godot type (the source generator relies on partial). The file/class name should match the node script.
3. Override lifecycle methods in PascalCase with double delta: _Ready(), _Process(double delta), _PhysicsProcess(double delta).
4. Expose tunables with [Export]; they show in the Inspector like GDScript @export.
5. Declare signals as [Signal] delegates named XxxEventHandler; emit with EmitSignal(SignalName.Xxx, ...) and subscribe with the generated C# event.
6. Get nodes with GetNode<T>("Path") (or %Unique), and call into GDScript with Call/Get/Set when needed.

Patterns

1. A node script: lifecycle, [Export], GetNode

using Godot;

public partial class Player : CharacterBody2D
{
    [Export] public float Speed = 200.0f;          // editable in the Inspector
    [Export] public float JumpVelocity = -400.0f;

    private const float Gravity = 1200.0f;
    private AnimatedSprite2D _sprite;

    public override void _Ready()
    {
        _sprite = GetNode<AnimatedSprite2D>("AnimatedSprite2D");
    }

    public override void _PhysicsProcess(double delta)
    {
        Vector2 v = Velocity;                       // Velocity is a property here
        if (!IsOnFloor())
            v.Y += Gravity * (float)delta;          // delta is double; cast for float math
        if (Input.IsActionJustPressed("jump") && IsOnFloor())
            v.Y = JumpVelocity;

        float dir = Input.GetAxis("move_left", "move_right");
        v.X = dir != 0 ? dir * Speed : Mathf.MoveToward(v.X, 0, Speed);

        Velocity = v;
        MoveAndSlide();                             // no args, like GDScript 4.x
    }
}