在 Python 中只从字符串中获取第一个数字
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/32571348/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
getting only the first Number from String in Python
提问by Serious Ruffy
I′m currently facing the problem that I have a string of which I want to extract only the first number. My first step was to extract the numbers from the string.
我目前面临的问题是我有一个我只想提取第一个数字的字符串。我的第一步是从字符串中提取数字。
Headline = "redirectDetail('27184','2 -New-York-Explorer-Pass')"
print (re.findall('\d+', headline ))
Output is ['27184', '2']
In this case it returned me two numbers but I only want to have the first one "27184".
在这种情况下，它返回了两个数字，但我只想拥有第一个“27184”。
Hence, I tried with the following code:
因此，我尝试使用以下代码：
print (re.findall('/^[^\d]*(\d+)/', headline ))
But It does not work:
但它不起作用：
Output:[]
Can you guys help me out? Any feedback is appreciated
你们能帮我吗？任何反馈表示赞赏
采纳答案by Avinash Raj
Just use re.searchwhich stops matching once it finds a match.
只需使用re.searchwhich 一旦找到匹配就停止匹配。
re.search(r'\d+', headline).group()
or
或者
You must remove the forward slashes present in your regex.
您必须删除正则表达式中存在的正斜杠。
re.findall(r'^\D*(\d+)', headline)
回答by Dylan Lawrence
re.search('[0-9]+', headline).group()
回答by David
Solution without regex (not necessarily better):
没有正则表达式的解决方案（不一定更好）：
import string
no_digits = string.printable[10:]
headline = "redirectDetail('27184','2 -New-York-Explorer-Pass')"
trans = str.maketrans(no_digits, " "*len(no_digits))
print(headline.translate(trans).split()[0])
>>> 27184
