问题描述
如何制作:
if str(variable) == [contains text]:
条件?
(或者什么,因为我很确定我刚才写的完全错了)
(or something, because I am pretty sure that what I just wrote is completely wrong)
我正在尝试检查列表中的 random.choice
是 ["",]
(空白)还是包含 ["text",]
.
I am sort of trying to check if a random.choice
from my list is ["",]
(blank) or contains ["text",]
.
推荐答案
你可以只比较你的字符串和空字符串:
You could just compare your string to the empty string:
if variable != "":
etc.
但你可以缩写如下:
if variable:
etc.
说明:if
实际上是通过计算您给它的逻辑表达式的值来工作的:True
或 False
.如果您只是使用变量名(或hello"之类的文字字符串)而不是逻辑测试,则规则是:空字符串计为 False,所有其他字符串计为 True.空列表和数字 0 也算作假,而其他大多数情况都算作真.
Explanation: An if
actually works by computing a value for the logical expression you give it: True
or False
. If you simply use a variable name (or a literal string like "hello") instead of a logical test, the rule is: An empty string counts as False, all other strings count as True. Empty lists and the number zero also count as false, and most other things count as true.
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