以数字之间的字符开头和结尾的正则表达式

Question

I have requirement in javascript where the starting and ending of a word is a Character with in between numbers. eg S652354536667U

I tried with pattern

(/[A-Z]\d+[A-Z]$/).test(S652354536667U) // returns true ok
(/[A-Z]\d+[A-Z]$/).test(S65235Y4536667U) // returns true needed false

but it is allowing characters in between like S65235Y4536667U is being accepted.

Any help is appreciated.

Thanks

Answer 1

You need to put a caret at the start of the regex, to indicate the first letter is at the start of the string, ie:

^[A-Z]\d+[A-Z]$

Answer 2

You are missing the ^ . It should be:

^[A-Z]\d*[A-Z]$

You can use this site to quickly test your regex: https://regexr.com/

Answer 3

You left caret in the beginning.

 ["S652354536667U", "S65235Y4536667U"].forEach(item => { console.log(/^[AZ]\d+[AZ]$/.test(item)) })

Answer 4

You need to put ^ at the start and $ at the end in the reg ex. Otherwise if the pattern match anywhere else in the input, it will return true

(/^[A-Z]\d+[A-Z]$/).test(S652354536667U) // returns true 
(/^[A-Z]\d+[A-Z]$/).test(S65235Y4536667U) // returns true 

Check the below image. It is without specifying the start position. So, from the character 'Y' matching the reg ex

Below is with the starting position