凉鞋的 Godot 笔记 201. 第三轮循环：引入变量

201. 第三轮循环：引入变量

在这一篇，我们进行第三轮编辑-测试循环。

在之前我们编写了输出 Hello Godot 的脚本，如下:

extends Node# Called when the node enters the scene tree for the first time.
func _ready():print("Hello Godot")pass # Replace with function body.# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):pass

如果我们要输出 10 次 Hello Godot 该怎么办呢？

答案很简单，就是复制十行 print(“Hello Godot”)，代码如下:

extends Node# Called when the node enters the scene tree for the first time.
func _ready():print("Hello Godot")print("Hello Godot")print("Hello Godot")print("Hello Godot")print("Hello Godot")print("Hello Godot")print("Hello Godot")print("Hello Godot")print("Hello Godot")print("Hello Godot")pass # Replace with function body.# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):pass

这样当我们运行次场景后，结果如下:

总共输出了十次 Hello Godot。

此时我突然想要把输出十次 Hello Godot 改成输出十次 Hello GDScript。

那么最简单的方式，就是直接修改代码，如下:

extends Node# Called when the node enters the scene tree for the first time.
func _ready():print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")print("Hello GDScript")pass # Replace with function body.# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):pass

运行之后结果如下:

但是这样太不优雅了，我们需要复制粘贴十次，如果我们有 100 个甚至 1000 个 Hello Godot，那么我们可能需要复制粘贴很多次，或者使用代码编辑器所提供的查找/替换功能完成。

比较优雅的方式就是引入一个变量，代码如下所示:

extends Node# Called when the node enters the scene tree for the first time.
func _ready():var text_to_print = "Hello GDScript"print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)pass # Replace with function body.# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):pass

这样当我们想要输出十次 Hello World 那么我们只需要修改变量的值即可，如下所示:

extends Node# Called when the node enters the scene tree for the first time.
func _ready():var text_to_print = "Hello World"print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)print(text_to_print)pass # Replace with function body.# Called every frame. 'delta' is the elapsed time since the previous frame.
func _process(delta):pass