Up to date

This page is up to date for Godot 4.3. If you still find outdated information, please open an issue.

C# exported properties

Dans Godot, les membres de classe peuvent être exportés. Cela signifie que leur valeur est sauvegardée avec la ressource (par exemple la scene) à laquelle ils sont attachés. Ils seront également disponibles pour l'édition dans l'éditeur de propriétés. L'exportation se fait en utilisant l'attribut export.

using Godot;

public partial class ExportExample : Node3D
{
    [Export]
    public int Number { get; set; } = 5;
}

In that example the value 5 will be saved, and after building the current project it will be visible in the property editor.

L'un des avantages fondamentaux de l'exportation des variables membres est de les rendre visibles et modifiables dans l'éditeur. De cette façon, les artistes et les game designers peuvent modifier les valeurs qui influenceront plus tard le fonctionnement du programme. Pour cela, une syntaxe spéciale d'exportation est fournie.

Exporting can only be done with Variant-compatible types.

Note

Exporting properties can also be done in GDScript, for information on that see GDScript Propriétés exportées.

Utilisation de base

L'exportation fonctionne avec les champs et les propriétés. Ils peuvent avoir n’importe quel modificateur d’accès.

[Export]
private int _number;

[Export]
public int Number { get; set; }

Exported members can specify a default value; otherwise, the default value of the type is used instead.

An int like Number defaults to 0. Text defaults to null because string is a reference type.

[Export]
public int Number { get; set; }

[Export]
public string Text { get; set; }

Default values can be specified for fields and properties.

[Export]
private string _greeting = "Hello World";

[Export]
public string Greeting { get; set; } = "Hello World";

Properties with a backing field use the default value of the backing field.

private int _number = 2;

[Export]
public int NumberWithBackingField
{
    get => _number;
    set => _number = value;
}

Note

A property's get is not actually executed to determine the default value. Instead, Godot analyzes the C# source code. This works fine for most cases, such as the examples on this page. However, some properties are too complex for the analyzer to understand.

For example, the following property attempts to use math to display the default value as 5 in the property editor, but it doesn't work:

[Export]
public int NumberWithBackingField
{
    get => _number + 3;
    set => _number = value - 3;
}

private int _number = 2;

The analyzer doesn't understand this code and falls back to the default value for int, 0. However, when running the scene or inspecting a node with an attached tool script, _number will be 2, and NumberWithBackingField will return 5. This difference may cause confusing behavior. To avoid this, don't use complex properties. Alternatively, if the default value can be explicitly specified, it can be overridden with the _PropertyCanRevert() and _PropertyGetRevert() methods.

Any type of Resource or Node can be exported. The property editor shows a user-friendly assignment dialog for these types. This can be used instead of GD.Load and GetNode. See Nodes and Resources.

[Export]
public PackedScene PackedScene { get; set; }

[Export]
public RigidBody2D RigidBody2D { get; set; }

Grouping exports

It is possible to group your exported properties inside the Inspector with the [ExportGroup] attribute. Every exported property after this attribute will be added to the group. Start a new group or use [ExportGroup("")] to break out.

[ExportGroup("My Properties")]
[Export]
public int Number { get; set; } = 3;

The second argument of the attribute can be used to only group properties with the specified prefix.

Groups cannot be nested, use [ExportSubgroup] to create subgroups within a group.

[ExportSubgroup("Extra Properties")]
[Export]
public string Text { get; set; } = "";
[Export]
public bool Flag { get; set; } = false;

You can also change the name of your main category, or create additional categories in the property list with the [ExportCategory] attribute.

[ExportCategory("Main Category")]
[Export]
public int Number { get; set; } = 3;
[Export]
public string Text { get; set; } = "";

[ExportCategory("Extra Category")]
[Export]
public bool Flag { get; set; } = false;

Note

The list of properties is organized based on the class inheritance, and new categories break that expectation. Use them carefully, especially when creating projects for public use.

Chaînes de caractères représentant des chemins

Property hints can be used to export strings as paths

Chaîne de caractères représentant un chemin vers un fichier.

[Export(PropertyHint.File)]
public string GameFile { get; set; }

Chaîne de caractères représentant un chemin vers un répertoire.

[Export(PropertyHint.Dir)]
public string GameDirectory { get; set; }

Chaîne de caractères représentant un chemin vers un fichier, avec un filtre personnalisé fourni comme indice.

[Export(PropertyHint.File, "*.txt,")]
public string GameFile { get; set; }

L'utilisation de chemins dans le système de fichiers global est également possible, mais uniquement dans les scripts en mode outil (tool).

Chaîne de caractères représentant un chemin vers un fichier dans le système de fichier global.

[Export(PropertyHint.GlobalFile, "*.png")]
public string ToolImage { get; set; }

Chaîne de caractères représentant un chemin vers un répertoire dans le système de fichier global.

[Export(PropertyHint.GlobalDir)]
public string ToolDir { get; set; }

L'annotation multiligne indique à l'éditeur d'afficher un grand champ de saisie pour l'édition sur plusieurs lignes.

[Export(PropertyHint.MultilineText)]
public string Text { get; set; }

Limitation des plages de saisie de l'éditeur

Using the range property hint allows you to limit what can be input as a value using the editor.

Autorise les valeurs entières de 0 à 20.

[Export(PropertyHint.Range, "0,20,")]
public int Number { get; set; }

Autorise les valeurs entières de -10 à 20.

[Export(PropertyHint.Range, "-10,20,")]
public int Number { get; set; }

Autorise les nombres à virgule flottante de -10 à 20 et aligne la valeur sur des multiples de 0,2.

[Export(PropertyHint.Range, "-10,20,0.2")]
public float Number { get; set; }

If you add the hints "or_greater" and/or "or_less" you can go above or below the limits when adjusting the value by typing it instead of using the slider.

[Export(PropertyHint.Range, "0,100,1,or_greater,or_less")]
public int Number { get; set; }

Nombre à virgule flottante avec indice d'assouplissement

Display a visual representation of the ease function when editing.

[Export(PropertyHint.ExpEasing)]
public float TransitionSpeed { get; set; }

Export with suffix hint

Display a unit hint suffix for exported variables. Works with numeric types, such as floats or vectors:

[Export(PropertyHint.None, "suffix:m/s\u00b2")]
public float Gravity { get; set; } = 9.8f;
[Export(PropertyHint.None, "suffix:m/s")]
public Vector3 Velocity { get; set; }

In the above example, \u00b2 is used to write the "squared" character (²).

Couleurs

Couleur classique donnée sous la forme de valeur rouge-vert-bleu-alpha.

[Export]
public Color Color { get; set; }

Couleur donnée sous la forme de valeur rouge-vert-bleu (alpha vaudra toujours 1).

[Export(PropertyHint.ColorNoAlpha)]
public Color Color { get; set; }

Nœuds

Since Godot 4.0, nodes can be directly exported without having to use NodePaths.

[Export]
public Node Node { get; set; }

A specific type of node can also be directly exported. The list of nodes shown after pressing "Assign" in the inspector is filtered to the specified type, and only a correct node can be assigned.

[Export]
public Sprite2D Sprite2D { get; set; }

Custom node classes can also be exported directly. The filtering behavior depends on whether the custom class is a global class.

L'exportation de NodePaths comme dans Godot 3.x est toujours possible, au cas où vous en auriez besoin :

[Export]
public NodePath NodePath { get; set; }

public override void _Ready()
{
    var node = GetNode(NodePath);
}

Ressources

[Export]
public Resource Resource { get; set; }

Dans l'inspecteur, vous pouvez ensuite faire glisser et déposer un fichier de ressources depuis le dock 'Système de fichier' dans l'emplacement de la variable.

Opening the inspector dropdown may result in an extremely long list of possible classes to create, however. Therefore, if you specify a type derived from Resource such as:

[Export]
public AnimationNode AnimationNode { get; set; }

The drop-down menu will be limited to AnimationNode and all its inherited classes. Custom resource classes can also be used, see Classes globales en C#.

Il faut noter que même si le script n'est pas exécuté pendant qu'il est dans l'éditeur, les propriétés exportées sont toujours modifiables. Ceci peut être utilisé en conjonction avec un script en mode "outil" (tool).

Exportation de bit flags

Members whose type is an enum with the [Flags] attribute can be exported and their values are limited to the members of the enum type. The editor will create a widget in the Inspector, allowing to select none, one, or multiple of the enum members. The value will be stored as an integer.

A flags enum uses powers of 2 for the values of the enum members. Members that combine multiple flags using logical OR (|) are also possible.

[Flags]
public enum SpellElements
{
    Fire = 1 << 1,
    Water = 1 << 2,
    Earth = 1 << 3,
    Wind = 1 << 4,

    FireAndWater = Fire | Water,
}

[Export]
public SpellElements MySpellElements { get; set; }

Integers used as bit flags can store multiple true/false (boolean) values in one property. By using the Flags property hint, any of the given flags can be set from the editor.

[Export(PropertyHint.Flags, "Fire,Water,Earth,Wind")]
public int SpellElements { get; set; } = 0;

You must provide a string description for each flag. In this example, Fire has value 1, Water has value 2, Earth has value 4 and Wind corresponds to value 8. Usually, constants should be defined accordingly (e.g. private const int ElementWind = 8 and so on).

You can add explicit values using a colon:

[Export(PropertyHint.Flags, "Self:4,Allies:8,Foes:16")]
public int SpellTargets { get; set; } = 0;

Only power of 2 values are valid as bit flags options. The lowest allowed value is 1, as 0 means that nothing is selected. You can also add options that are a combination of other flags:

[Export(PropertyHint.Flags, "Self:4,Allies:8,Self and Allies:12,Foes:16")]
public int SpellTargets { get; set; } = 0;

Des annotations d'exportation sont également fournies pour les couches physiques et de rendu définies dans les paramètres du projet.

[Export(PropertyHint.Layers2DPhysics)]
public uint Layers2DPhysics { get; set; }
[Export(PropertyHint.Layers2DRender)]
public uint Layers2DRender { get; set; }
[Export(PropertyHint.Layers3DPhysics)]
public uint Layers3DPhysics { get; set; }
[Export(PropertyHint.Layers3DRender)]
public uint Layers3DRender { get; set; }

L'utilisation de bit flags nécessite une certaine compréhension des opérations sur les bits. En cas de doute, utilisez des variables booléennes à la place.

Exportation d'énumérations

Members whose type is an enum can be exported and their values are limited to the members of the enum type. The editor will create a widget in the Inspector, enumerating the following as "Thing 1", "Thing 2", "Another Thing". The value will be stored as an integer.

public enum MyEnum
{
    Thing1,
    Thing2,
    AnotherThing = -1,
}

[Export]
public MyEnum MyEnum { get; set; }

Integer and string members can also be limited to a specific list of values using the [Export] annotation with the PropertyHint.Enum hint. The editor will create a widget in the Inspector, enumerating the following as Warrior, Magician, Thief. The value will be stored as an integer, corresponding to the index of the selected option (i.e. 0, 1, or 2).

[Export(PropertyHint.Enum, "Warrior,Magician,Thief")]
public int CharacterClass { get; set; }

You can add explicit values using a colon:

[Export(PropertyHint.Enum, "Slow:30,Average:60,Very Fast:200")]
public int CharacterSpeed { get; set; }

If the type is string, the value will be stored as a string.

[Export(PropertyHint.Enum, "Rebecca,Mary,Leah")]
public string CharacterName { get; set; }

If you want to set an initial value, you must specify it explicitly:

[Export(PropertyHint.Enum, "Rebecca,Mary,Leah")]
public string CharacterName { get; set; } = "Rebecca";

Exporting collections

As explained in the C# Variant documentation, only certain C# arrays and the collection types defined in the Godot.Collections namespace are Variant-compatible, therefore, only those types can be exported.

Exporting Godot arrays

[Export]
public Godot.Collections.Array Array { get; set; }

Using the generic Godot.Collections.Array<T> allows specifying the type of the array elements, which will be used as a hint for the editor. The Inspector will restrict the elements to the specified type.

[Export]
public Godot.Collections.Array<string> Array { get; set; }

The default value of Godot arrays is null. A different default can be specified:

[Export]
public Godot.Collections.Array<string> CharacterNames { get; set; } = new Godot.Collections.Array<string>
{
    "Rebecca",
    "Mary",
    "Leah",
};

Les tableaux avec des types spécifiés qui héritent de Resource peuvent être définis en faisant glisser et en déposant plusieurs fichiers depuis le dock 'Système de fichiers'.

[Export]
public Godot.Collections.Array<Texture> Textures { get; set; }

[Export]
public Godot.Collections.Array<PackedScene> Scenes { get; set; }

Exporting Godot dictionaries

[Export]
public Godot.Collections.Dictionary Dictionary { get; set; }

Using the generic Godot.Collections.Dictionary<TKey, TValue> allows specifying the types of the key and value elements of the dictionary.

Note

Typed dictionaries are currently unsupported in the Godot editor, so the Inspector will not restrict the types that can be assigned, potentially resulting in runtime exceptions.

[Export]
public Godot.Collections.Dictionary<string, int> Dictionary { get; set; }

The default value of Godot dictionaries is null. A different default can be specified:

[Export]
public Godot.Collections.Dictionary<string, int> CharacterLives { get; set; } = new Godot.Collections.Dictionary<string, int>
{
    ["Rebecca"] = 10,
    ["Mary"] = 42,
    ["Leah"] = 0,
};

Exporting C# arrays

C# arrays can exported as long as the element type is a Variant-compatible type.

[Export]
public Vector3[] Vectors { get; set; }

[Export]
public NodePath[] NodePaths { get; set; }

The default value of C# arrays is null. A different default can be specified:

[Export]
public Vector3[] Vectors { get; set; } = new Vector3[]
{
    new Vector3(1, 2, 3),
    new Vector3(3, 2, 1),
}

Définition des variables exportées à partir d'un script tool(outil)

When changing an exported variable's value from a script in Mode tool(outil), the value in the inspector won't be updated automatically. To update it, call NotifyPropertyListChanged() after setting the exported variable's value.

Exportations avancées

Tous les types d'exportation ne peuvent pas être fournis au niveau du langage lui-même pour éviter une complexité de conception inutile. Ce qui suit décrit quelques fonctions d'exportation plus ou moins courantes qui peuvent être mises en œuvre avec une API de bas niveau.

Before reading further, you should get familiar with the way properties are handled and how they can be customized with _Set(), _Get(), and _GetPropertyList() methods as described in Accès aux données ou à la logique à partir d'un objet.

Voir aussi

Pour les propriétés de liaison utilisant les méthodes ci-dessus en C++, voir Liaison (Binding) des propriétés à l'aide de _set/_get/_get_property_list.

Avertissement

Le script doit fonctionner en mode tool pour que les méthodes ci-dessus puissent fonctionner dans l'éditeur.