正则表达式在某些情况下允许值1到100

Question

i want a regex to allow 1-3 digits whole number,it should not start with 0 and should be a whole number,not decimals or fractions or any signed values,

this is what i have tried

"/^(\s*|\d{1,3})$/"

but it does not seem to work..

thanks in advance

Answer 1

You can do it like this:

^(([1-9]\d?)|100)$

This would ensure that

• There is at least one digit
• That multi-digit numbers start in a digit other than zero
• That the only allowed three-digit number is 100.

Answer 2

^[1-9][0-9]\{,2\}$

It should be indeed end of line; end-of word will get the fractional part.