如何匹配字符串的开头和结尾？

Question

I try to match space at the start and the end of string, I tried many regexes but nothing worked, this is my basic regex:

^\s\s$

Any help or hint please? I would like to not give me the answer directly, just useful hints will be useful.

Answer 1

Your current regex will match things like 2 spaces, because that's what your regex says:

start of string, whitespace, whitespace, end of string

To match spaces both at the start and at the end, you need to use the | to mean "or". If the whitespace is either at the start or the end, we match it:

^\s|\s$

If you want to match multiple spaces:

^\s+|\s+$