Python：如何使用 Pygame 显示的函数调用切换大小写

Question

我正在尝试做一个简单的应用程序，用不同的参数调用相同的函数。

这是代码片段：

def text_objects(text, font):
    textSurface = font.render(text, True, black)
    return textSurface, textSurface.get_rect()

def message_display(text, size, x, y): 
    #print(pygame.font.get_fonts())
    font = pygame.font.Font(None, size) 
    text_surface, text_rectangle = text_objects(text, font) 
    text_rectangle.center = (x, y) 
    gameDisplay.blit(text_surface, text_rectangle) 

def countdown(count_case):
    
    print("Checking Case")
    print(count_case)

    switcher={
            1: message_display("starting in 5", 40, display_width / 2, (display_height + 400) / 2),
            2: message_display("starting in 4", 40, display_width / 2, (display_height + 400) / 2),
            3: message_display("starting in 3", 40, display_width / 2, (display_height + 400) / 2),
            4: message_display("starting in 2", 40, display_width / 2, (display_height + 400) / 2),
            5: message_display("starting in 1", 40, display_width / 2, (display_height + 400) / 2)
            }
    func = switcher.get(count_case,"Invalid Countdown")
    return func()

我能够初始化 Pygame 屏幕并通过检查 print().

将 count_case 正确地传递到 countdown() 函数中

但是，我主要不知道根据 count_case 的值正确调用和执行 message_display 函数的语法； 1 到 5。提前致谢。

Answer 1

表达式

message_display("starting in 5", 40, display_width / 2, (display_height + 400) / 2)

是函数调用。因此，您实际上将 message_display 的 return 值存储在字典中。只需存储一个带有参数的元组：

switcher = {
    1: ("starting in 5", 40, display_width / 2, (display_height + 400) / 2),
    2: ("starting in 4", 40, display_width / 2, (display_height + 400) / 2),
    3: ("starting in 3", 40, display_width / 2, (display_height + 400) / 2),
    4: ("starting in 2", 40, display_width / 2, (display_height + 400) / 2),
    5: ("starting in 1", 40, display_width / 2, (display_height + 400) / 2)
}

使用星号 (*) 运算符 ("unzip") 调用函数：

message_display(*switcher[count_case])

countdown 函数:

def countdown(count_case):
    
    print("Checking Case")
    print(count_case)

    switcher={
        1: ("starting in 5", 40, display_width // 2, (display_height + 400) // 2),
        2: ("starting in 4", 40, display_width // 2, (display_height + 400) // 2),
        3: ("starting in 3", 40, display_width // 2, (display_height + 400) // 2),
        4: ("starting in 2", 40, display_width // 2, (display_height + 400) // 2),
        5: ("starting in 1", 40, display_width // 2, (display_height + 400) // 2)
    }
    return message_display(*switcher[count_case])

Answer 2

您根本不需要 dict/switch。您可以改为根据输入格式化显示的字符串

def countdown(count_case):
    if count_case < 1 or count_case > 5:
        raise ValueError("count_case must be between 1 and 5")
    return message_display(f"starting in {6 - count_case}", 40, display_width / 2, (display_height + 400) / 2)

Python：如何使用 Pygame 显示的函数调用切换大小写

Python: How to Switch Case with Function Call for Pygame Display

python

pygame

function

switch-statement