如何在一行中组合多个if语句

Question

你好，我是python和编程的新手，我该如何将这些组合起来呢?

if "Web" in source:
source = "WEB"
if ((source == "Blu-ray") and (other == "Remux") and (reso == "1080p")):
reso = "BD Remux"
if "DVD" in name:
reso = "DVD Remux"
if ((source == "Ultra HD Blu-ray") and (other == "Remux") and (reso == "2160p")):
reso = "UHD Remux"
if source == "Ultra HD Blu-ray":
source = "Blu-ray"

Answer 1

您可以使用elif子句扩展if语句，并添加额外的条件:

mystring='what will it print?' 
if   mystring == 'hello':
print('world!')
elif mystring == 'good':
print('bye!')
elif mystring == 'how':
print('are you?')
else:
print('I ran out of ideas!')

[out]: I ran out of ideas!

稍微重写一下你的例子可以像下面这样:

source='Ultra HD Blu-ray'
name='DVD'
reso='2160p'
other='Remux'
resos={'1080p':'BD Remux','2160p':'UHD Remux'}
if "Web" in source:
source = "WEB"
elif "Blu-ray" in source and other == "Remux":
source = "Blu-ray"
reso   = resos.get(reso,'UNDEFINED')
elif "DVD" in name:
reso = "DVD Remux"
print(source, name, reso)

[out]: Blu-ray DVD UHD Remux

请注意，我使用resos字典来替换两个if声明，这里有更多详细信息。

Answer 2

将这么多语句合并到一行(问题是一行吗?)可能不会是"python式的"。括号也是不必要的。

if "Web" in source:
source = "WEB"
elif source == "Blu-ray" and other == "Remux" and reso == "1080p":
reso = "BD Remux"
elif "DVD" in name:
reso = "DVD Remux"
elif source == "Ultra HD Blu-ray" and other == "Remux" and reso == "2160p":
reso = "UHD Remux"
elif source == "Ultra HD Blu-ray":
source = "Blu-ray"
else:
source = ""
reso = ""