Merge pull request #64930 from raulsntos/dotnet/docs

Update C# signal documentation and remove bind array

Author: akien-mga

doc/classes/Callable.xml

@@ -18,17 +18,19 @@
 		    callable.call("invalid")  # Invalid call, should have at least 2 arguments.
 		[/gdscript]
 		[csharp]
-		public void PrintArgs(object arg1, object arg2, object arg3 = null)
+		// Default parameter values are not supported.
+		public void PrintArgs(Variant arg1, Variant arg2, Variant arg3 = default)
 		{
 		    GD.PrintS(arg1, arg2, arg3);
 		}
 
 		public void Test()
 		{
-		    Callable callable = new Callable(this, nameof(PrintArgs));
-		    callable.Call("hello", "world"); // Prints "hello world null".
+		    // Invalid calls fail silently.
+		    Callable callable = new Callable(this, MethodName.PrintArgs);
+		    callable.Call("hello", "world"); // Default parameter values are not supported, should have 3 arguments.
 		    callable.Call(Vector2.Up, 42, callable); // Prints "(0, -1) 42 Node(Node.cs)::PrintArgs".
-		    callable.Call("invalid"); // Invalid call, should have at least 2 arguments.
+		    callable.Call("invalid"); // Invalid call, should have 3 arguments.
 		}
 		[/csharp]
 		[/codeblocks]

doc/classes/EditorCommandPalette.xml

@@ -16,7 +16,7 @@
 		[csharp]
 		EditorCommandPalette commandPalette = GetEditorInterface().GetCommandPalette();
 		// ExternalCommand is a function that will be called with the command is executed.
-		Callable commandCallable = new Callable(this, nameof(ExternalCommand));
+		Callable commandCallable = new Callable(this, MethodName.ExternalCommand);
 		commandPalette.AddCommand("command", "test/command", commandCallable)
 		[/csharp]
 		[/codeblocks]

doc/classes/Expression.xml

@@ -28,7 +28,7 @@
 
 		public override void _Ready()
 		{
-		    GetNode("LineEdit").TextSubmitted += OnTextEntered;
+		    GetNode<LineEdit>("LineEdit").TextSubmitted += OnTextEntered;
 		}
 
 		private void OnTextEntered(string command)

doc/classes/HTTPRequest.xml

@@ -69,7 +69,7 @@
 		}
 
 		// Called when the HTTP request is completed.
-		private void HttpRequestCompleted(int result, int response_code, string[] headers, byte[] body)
+		private void HttpRequestCompleted(int result, int responseCode, string[] headers, byte[] body)
 		{
 		    var json = new JSON();
 		    json.Parse(body.GetStringFromUTF8());
@@ -128,7 +128,7 @@
 		}
 
 		// Called when the HTTP request is completed.
-		private void HttpRequestCompleted(int result, int response_code, string[] headers, byte[] body)
+		private void HttpRequestCompleted(int result, int responseCode, string[] headers, byte[] body)
 		{
 		    if (result != (int)HTTPRequest.Result.Success)
 		    {

doc/classes/Object.xml

@@ -305,7 +305,7 @@
 				[/gdscript]
 				[csharp]
 				var node = new Node3D();
-				node.Call("rotate", new Vector3(1f, 0f, 0f), 1.571f);
+				node.Call(Node3D.MethodName.Rotate, new Vector3(1f, 0f, 0f), 1.571f);
 				[/csharp]
 				[/codeblocks]
 				[b]Note:[/b] In C#, [param method] must be in snake_case when referring to built-in Godot methods. Prefer using the names exposed in the [code]MethodName[/code] class to avoid allocating a new [StringName] on each call.
@@ -323,7 +323,7 @@
 				[/gdscript]
 				[csharp]
 				var node = new Node3D();
-				node.CallDeferred("rotate", new Vector3(1f, 0f, 0f), 1.571f);
+				node.CallDeferred(Node3D.MethodName.Rotate, new Vector3(1f, 0f, 0f), 1.571f);
 				[/csharp]
 				[/codeblocks]
 				[b]Note:[/b] In C#, [param method] must be in snake_case when referring to built-in Godot methods. Prefer using the names exposed in the [code]MethodName[/code] class to avoid allocating a new [StringName] on each call.
@@ -342,7 +342,7 @@
 				[/gdscript]
 				[csharp]
 				var node = new Node3D();
-				node.Callv("rotate", new Godot.Collections.Array { new Vector3(1f, 0f, 0f), 1.571f });
+				node.Callv(Node3D.MethodName.Rotate, new Godot.Collections.Array { new Vector3(1f, 0f, 0f), 1.571f });
 				[/csharp]
 				[/codeblocks]
 				[b]Note:[/b] In C#, [param method] must be in snake_case when referring to built-in Godot methods. Prefer using the names exposed in the [code]MethodName[/code] class to avoid allocating a new [StringName] on each call
@@ -394,8 +394,8 @@
 
 				    // This assumes that a `Player` class exists, which defines a `Hit` signal.
 				    var player = new Player();
-				    // Signals as events (`player.Hit += OnPlayerHit;`) do not support argument binding. You have to use:
-				    player.Hit.Connect(OnPlayerHit, new Godot.Collections.Array {"sword", 100 });
+				    // We can use lambdas when we need to bind additional parameters.
+				    player.Hit += () => OnPlayerHit("sword", 100);
 				}
 
 				private void OnButtonDown()
@@ -405,7 +405,7 @@
 
 				private void OnPlayerHit(string weaponType, int damage)
 				{
-				    GD.Print(String.Format("Hit with weapon {0} for {1} damage.", weaponType, damage));
+				    GD.Print($"Hit with weapon {weaponType} for {damage} damage.");
 				}
 				[/csharp]
 				[/codeblocks]
@@ -431,16 +431,12 @@
 				public override void _Ready()
 				{
 				    var button = new Button();
-				    // Option 1: Object.Connect() with an implicit Callable for the defined function.
-				    button.Connect("button_down", OnButtonDown);
-				    // Option 2: Object.connect() with a constructed Callable using a target object and method name.
-				    button.Connect("button_down", new Callable(self, nameof(OnButtonDown)));
-				    // Option 3: Signal.connect() with an implicit Callable for the defined function.
-				    button.ButtonDown.Connect(OnButtonDown);
-				    // Option 3b: In C#, we can use signals as events and connect with this more idiomatic syntax:
+				    // Option 1: In C#, we can use signals as events and connect with this idiomatic syntax:
 				    button.ButtonDown += OnButtonDown;
-				    // Option 4: Signal.connect() with a constructed Callable using a target object and method name.
-				    button.ButtonDown.Connect(new Callable(self, nameof(OnButtonDown)));
+				    // Option 2: Object.Connect() with a constructed Callable from a method group.
+				    button.Connect(Button.SignalName.ButtonDown, Callable.From(OnButtonDown));
+				    // Option 3: Object.Connect() with a constructed Callable using a target object and method name.
+				    button.Connect(Button.SignalName.ButtonDown, new Callable(this, MethodName.OnButtonDown));
 				}
 
 				private void OnButtonDown()
@@ -458,6 +454,7 @@
 				func _ready():
 				    # This assumes that a `Player` class exists, which defines a `hit` signal.
 				    var player = Player.new()
+				    # Using Callable.bind().
 				    player.hit.connect(_on_player_hit.bind("sword", 100))
 
 				    # Parameters added when emitting the signal are passed first.
@@ -473,20 +470,19 @@
 				{
 				    // This assumes that a `Player` class exists, which defines a `Hit` signal.
 				    var player = new Player();
-				    // Option 1: Using Callable.Bind(). This way we can still use signals as events.
-				    player.Hit += OnPlayerHit.Bind("sword", 100);
-				    // Option 2: Using a `binds` Array in Signal.Connect().
-				    player.Hit.Connect(OnPlayerHit, new Godot.Collections.Array{ "sword", 100 });
+				    // Using lambda expressions that create a closure that captures the additional parameters.
+				    // The lambda only receives the parameters defined by the signal's delegate.
+				    player.Hit += (hitBy, level) => OnPlayerHit(hitBy, level, "sword", 100);
 
 				    // Parameters added when emitting the signal are passed first.
-				    player.EmitSignal("hit", "Dark lord", 5);
+				    player.EmitSignal(SignalName.Hit, "Dark lord", 5);
 				}
 
 				// We pass two arguments when emitting (`hit_by`, `level`),
 				// and bind two more arguments when connecting (`weapon_type`, `damage`).
 				private void OnPlayerHit(string hitBy, int level, string weaponType, int damage)
 				{
-				    GD.Print(String.Format("Hit by {0} (level {1}) with weapon {2} for {3} damage.", hitBy, level, weaponType, damage));
+				    GD.Print($"Hit by {hitBy} (level {level}) with weapon {weaponType} for {damage} damage.");
 				}
 				[/csharp]
 				[/codeblocks]
@@ -512,8 +508,8 @@
 				emit_signal("game_over")
 				[/gdscript]
 				[csharp]
-				EmitSignal("Hit", "sword", 100);
-				EmitSignal("GameOver");
+				EmitSignal(SignalName.Hit, "sword", 100);
+				EmitSignal(SignalName.GameOver);
 				[/csharp]
 				[/codeblocks]
 				[b]Note:[/b] In C#, [param signal] must be in snake_case when referring to built-in Godot signals. Prefer using the names exposed in the [code]SignalName[/code] class to avoid allocating a new [StringName] on each call.
@@ -581,7 +577,7 @@
 				var b = node.GetIndexed("position:y"); // b is -10
 				[/csharp]
 				[/codeblocks]
-				[b]Note:[/b] In C#, [param property_path] must be in snake_case when referring to built-in Godot properties.
+				[b]Note:[/b] In C#, [param property_path] must be in snake_case when referring to built-in Godot properties. Prefer using the names exposed in the [code]PropertyName[/code] class to avoid allocating a new [StringName] on each call.
 				[b]Note:[/b] This method does not support actual paths to nodes in the [SceneTree], only sub-property paths. In the context of nodes, use [method Node.get_node_and_resource] instead.
 			</description>
 		</method>
@@ -868,7 +864,7 @@
 				GD.Print(node.Position); // Prints (42, -10)
 				[/csharp]
 				[/codeblocks]
-				[b]Note:[/b] In C#, [param property_path] must be in snake_case when referring to built-in Godot properties.
+				[b]Note:[/b] In C#, [param property_path] must be in snake_case when referring to built-in Godot properties. Prefer using the names exposed in the [code]PropertyName[/code] class to avoid allocating a new [StringName] on each call.
 			</description>
 		</method>
 		<method name="set_message_translation">

doc/classes/Performance.xml

@@ -45,7 +45,7 @@
 				[csharp]
 				public override void _Ready()
 				{
-				    var monitorValue = new Callable(this, nameof(GetMonitorValue));
+				    var monitorValue = new Callable(this, MethodName.GetMonitorValue);
 
 				    // Adds monitor with name "MyName" to category "MyCategory".
 				    Performance.AddCustomMonitor("MyCategory/MyMonitor", monitorValue);

doc/classes/Signal.xml

@@ -16,12 +16,12 @@
 		[/gdscript]
 		[csharp]
 		[Signal]
-		delegate void Attacked();
+		delegate void AttackedEventHandler();
 
 		// Additional arguments may be declared.
 		// These arguments must be passed when the signal is emitted.
 		[Signal]
-		delegate void ItemDropped(itemName: string, amount: int);
+		delegate void ItemDroppedEventHandler(string itemName, int amount);
 		[/csharp]
 		[/codeblocks]
 	</description>

doc/classes/Tween.xml

@@ -19,7 +19,7 @@
 		Tween tween = GetTree().CreateTween();
 		tween.TweenProperty(GetNode("Sprite"), "modulate", Colors.Red, 1.0f);
 		tween.TweenProperty(GetNode("Sprite"), "scale", Vector2.Zero, 1.0f);
-		tween.TweenCallback(new Callable(GetNode("Sprite").QueueFree));
+		tween.TweenCallback(Callable.From(GetNode("Sprite").QueueFree));
 		[/csharp]
 		[/codeblocks]
 		This sequence will make the [code]$Sprite[/code] node turn red, then shrink, before finally calling [method Node.queue_free] to free the sprite. [Tweener]s are executed one after another by default. This behavior can be changed using [method parallel] and [method set_parallel].
@@ -35,7 +35,7 @@
 		Tween tween = GetTree().CreateTween();
 		tween.TweenProperty(GetNode("Sprite"), "modulate", Colors.Red, 1.0f).SetTrans(Tween.TransitionType.Sine);
 		tween.TweenProperty(GetNode("Sprite"), "scale", Vector2.Zero, 1.0f).SetTrans(Tween.TransitionType.Bounce);
-		tween.TweenCallback(new Callable(GetNode("Sprite").QueueFree));
+		tween.TweenCallback(Callable.From(GetNode("Sprite").QueueFree));
 		[/csharp]
 		[/codeblocks]
 		Most of the [Tween] methods can be chained this way too. In the following example the [Tween] is bound to the running script's node and a default transition is set for its [Tweener]s:
@@ -50,7 +50,7 @@
 		var tween = GetTree().CreateTween().BindNode(this).SetTrans(Tween.TransitionType.Elastic);
 		tween.TweenProperty(GetNode("Sprite"), "modulate", Colors.Red, 1.0f);
 		tween.TweenProperty(GetNode("Sprite"), "scale", Vector2.Zero, 1.0f);
-		tween.TweenCallback(new Callable(GetNode("Sprite").QueueFree));
+		tween.TweenCallback(Callable.From(GetNode("Sprite").QueueFree));
 		[/csharp]
 		[/codeblocks]
 		Another interesting use for [Tween]s is animating arbitrary sets of objects:
@@ -281,7 +281,7 @@
 				[/gdscript]
 				[csharp]
 				Tween tween = GetTree().CreateTween().SetLoops();
-				tween.TweenCallback(new Callable(Shoot)).SetDelay(1.0f);
+				tween.TweenCallback(Callable.From(Shoot)).SetDelay(1.0f);
 				[/csharp]
 				[/codeblocks]
 				[b]Example:[/b] Turning a sprite red and then blue, with 2 second delay:
@@ -294,8 +294,8 @@
 				[csharp]
 				Tween tween = GetTree().CreateTween();
 				Sprite2D sprite = GetNode<Sprite2D>("Sprite");
-				tween.TweenCallback(new Callable(() => sprite.Modulate = Colors.Red)).SetDelay(2.0f);
-				tween.TweenCallback(new Callable(() => sprite.Modulate = Colors.Blue)).SetDelay(2.0f);
+				tween.TweenCallback(Callable.From(() => sprite.Modulate = Colors.Red)).SetDelay(2.0f);
+				tween.TweenCallback(Callable.From(() => sprite.Modulate = Colors.Blue)).SetDelay(2.0f);
 				[/csharp]
 				[/codeblocks]
 			</description>
@@ -332,10 +332,10 @@
 				[csharp]
 				Tween tween = CreateTween().SetLoops();
 				tween.TweenProperty(GetNode("Sprite"), "position:x", 200.0f, 1.0f).AsRelative();
-				tween.TweenCallback(new Callable(Jump));
+				tween.TweenCallback(Callable.From(Jump));
 				tween.TweenInterval(2.0f);
 				tween.TweenProperty(GetNode("Sprite"), "position:x", -200.0f, 1.0f).AsRelative();
-				tween.TweenCallback(new Callable(Jump));
+				tween.TweenCallback(Callable.From(Jump));
 				tween.TweenInterval(2.0f);
 				[/csharp]
 				[/codeblocks]
@@ -357,7 +357,7 @@
 				[/gdscript]
 				[csharp]
 				Tween tween = CreateTween();
-				tween.TweenMethod(new Callable(() =&gt; LookAt(Vector3.Up)), new Vector3(-1.0f, 0.0f, -1.0f), new Vector3(1.0f, 0.0f, -1.0f), 1.0f); // The LookAt() method takes up vector as second argument.
+				tween.TweenMethod(Callable.From(() =&gt; LookAt(Vector3.Up)), new Vector3(-1.0f, 0.0f, -1.0f), new Vector3(1.0f, 0.0f, -1.0f), 1.0f); // The LookAt() method takes up vector as second argument.
 				[/csharp]
 				[/codeblocks]
 				[b]Example:[/b] Setting the text of a [Label], using an intermediate method and after a delay:
@@ -376,7 +376,7 @@
 				    base._Ready();
 
 				    Tween tween = CreateTween();
-				    tween.TweenMethod(new Callable(SetLabelText), 0.0f, 10.0f, 1.0f).SetDelay(1.0f);
+				    tween.TweenMethod(Callable.From&lt;int&gt;(SetLabelText), 0.0f, 10.0f, 1.0f).SetDelay(1.0f);
 				}
 
 				private void SetLabelText(int value)

doc/classes/UndoRedo.xml

@@ -48,10 +48,10 @@
 		{
 		    var node = GetNode<Node2D>("MyNode2D");
 		    UndoRedo.CreateAction("Move the node");
-		    UndoRedo.AddDoMethod(this, nameof(DoSomething));
-		    UndoRedo.AddUndoMethod(this, nameof(UndoSomething));
-		    UndoRedo.AddDoProperty(node, "position", new Vector2(100, 100));
-		    UndoRedo.AddUndoProperty(node, "position", node.Position);
+		    UndoRedo.AddDoMethod(this, MethodName.DoSomething);
+		    UndoRedo.AddUndoMethod(this, MethodName.UndoSomething);
+		    UndoRedo.AddDoProperty(node, Node2D.PropertyName.Position, new Vector2(100, 100));
+		    UndoRedo.AddUndoProperty(node, Node2D.PropertyName.Position, node.Position);
 		    UndoRedo.CommitAction();
 		}
 		[/csharp]