14.类资源

以文件形式存储的类被视为 resources。必须从磁盘加载它们，才能在其他类中访问它们。这可以使用 load 或 preload 函数来完成(见下面)。加载类资源的实例化是通过调用类对象上的 new函数来完成的:

# Load the class resource when calling load().
var my_class = load("myclass.gd")

# Preload the class only once at compile time.
const MyClass = preload("myclass.gd")

func _init():
    var a = MyClass.new()
    a.some_function()

导出

类成员可以导出。这意味着它们的值与它们所连接的资源一起被保存(例如 scene)。它们还可以在属性编辑器中进行编辑。导出是通过使用“导出”关键字:

extends Button

export var number = 5 # Value will be saved and visible in the property editor.

导出的变量必须初始化为常量表达式，或者以导出关键字参数的形式具有导出提示(参见下面)。

导出成员变量的基本好处之一是使它们在编辑器中可见并可编辑。通过这种方式，艺术家和游戏设计师可以修改影响程序运行的值。为此，提供了一种特殊的导出语法。

# If the exported value assigns a constant or constant expression,
# the type will be inferred and used in the editor.

export var number = 5

# Export can take a basic data type as an argument, which will be
# used in the editor.

export(int) var number

# Export can also take a resource type to use as a hint.

export(Texture) var character_face
export(PackedScene) var scene_file

# Integers and strings hint enumerated values.

# Editor will enumerate as 0, 1 and 2.
export(int, "Warrior", "Magician", "Thief") var character_class
# Editor will enumerate with string names.
export(String, "Rebecca", "Mary", "Leah") var character_name

# Named Enum Values

# Editor will enumerate as THING_1, THING_2, ANOTHER_THING.
enum NamedEnum {THING_1, THING_2, ANOTHER_THING = -1}
export (NamedEnum) var x

# Strings as Paths

# String is a path to a file.
export(String, FILE) var f
# String is a path to a directory.
export(String, DIR) var f
# String is a path to a file, custom filter provided as hint.
export(String, FILE, "*.txt") var f

# Using paths in the global filesystem is also possible,
# but only in tool scripts (see further below).

# String is a path to a PNG file in the global filesystem.
export(String, FILE, GLOBAL, "*.png") var tool_image
# String is a path to a directory in the global filesystem.
export(String, DIR, GLOBAL) var tool_dir

# The MULTILINE setting tells the editor to show a large input
# field for editing over multiple lines.
export(String, MULTILINE) var text

# Limiting editor input ranges

# Allow integer values from 0 to 20.
export(int, 20) var i
# Allow integer values from -10 to 20.
export(int, -10, 20) var j
# Allow floats from -10 to 20, with a step of 0.2.
export(float, -10, 20, 0.2) var k
# Allow values y = exp(x) where y varies between 100 and 1000
# while snapping to steps of 20. The editor will present a
# slider for easily editing the value.
export(float, EXP, 100, 1000, 20) var l

# Floats with Easing Hint

# Display a visual representation of the ease() function
# when editing.
export(float, EASE) var transition_speed

# Colors

# Color given as Red-Green-Blue value
export(Color, RGB) var col # Color is RGB.
# Color given as Red-Green-Blue-Alpha value
export(Color, RGBA) var col # Color is RGBA.

# Another node in the scene can be exported, too.

export(NodePath) var node

必须注意的是，即使脚本在编辑器中没有运行，导出的属性仍然是可编辑的(参见下面的“工具”)。