JS 正则表达式字符串不会以句点/点结尾

Question

I would like to have a validation for a particular string but it can't end up with a period/dot, how could you achieve that?

Valid string:

• .string
• ._string
• string
• stri.ng
• st_ring
• st._ring
• st_ri_ng

Invalid string:

• string.
• _string.
• stri.ng.
• st_ring.
• st._ring.
• st_ri_ng.

Answer 1

The pattern you are looking for is /[^.]$/ .

However, I must ask: does it need to be regex? If not, you can just read the last character and compare it to "." .

Answer 2

It would be much more efficient to use the endsWith method:

var validString = '.string';
var invalidString = 'string.';

validString.endsWith('.'); //false
invalidString.endsWith('.'); //true