how can I check the input is only number and white space in regular expression?

问题

I have "222 22 222", "333 33 33 333", "1234/34", and "ab345 543" and I want to check whether these inputs are numeric and white space. I.E this case, the first and the second inputs should return True by using method Test of Regular Expression, or return its own value by using Exec method. The third and the fourth should return false. How could I do so in Regular Expression? Please help. Thank you.

回答1:

You can test with this regular expression:

/^[\d\s]+$/

Rubular

---

If you want to also check that there is at least one digit in the string:

/^\s*\d[\d\s]*$/

回答2:

You can use something like this regex: ^(?:[0-9]|\s)*$

Here's a test case in python:

test=["222 22 222", "333 33 33 333", "1234/34","ab345 543"]
for i in test:
    m = re.match("^(?:[0-9]|\s)*$", i)
    if (m == None): print("False")
    else: print("True: %s" % m.group())

The resut is:

True: 222 22 222
True: 333 33 33 333
False
False

Cheers Andrea

回答3:

I think it should be something like [\d\s{0,1}]

来源：https://stackoverflow.com/questions/3656869/how-can-i-check-the-input-is-only-number-and-white-space-in-regular-expression