Regular matching: starting with a lowercase letter, ending with a lowercase letter, and there can be a dash (-) in the middle with a length less than 32 characters
var ss = /^[a-z]+([A-Za-z0-9_]|(-?)|[a-z]+$){1,31}/;
str="ss-fjdkkldjkskjdskjdksjdkjdkjklskssdkdkffdkdfkdfk";
ss.test(str);The result returned is
true
Normally it should return false.
{1,31} means that the range before matching is between 1 and 31. Why is the matching incorrect?
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My understanding of this regular expression is that it starts with the letters a-z, and then the content in () appears 1 to 31 times.
() means A-Z a-z 0-9 _ - any one of them can appear >= 1 time
The regular expression can be written like this