检查一个字符串是以一个字母开头，后跟数字，然后是任何字符

Question

How can I make the pattern below return true in scenarios like these:

m1 , m1a , M100bc , s45 , S396xyz

and false in scenarios like these:

'' , m , 1 , 1a , mm , Mx , mm1 , SS1b

Pattern to tweak: /^m\\S\\.*/i.test(text)

Right now it takes any number of letters at the start and non-digits right after the first letter

Answer 1

You may use

/^[a-z]\d.*/i

See the regex demo . If the string can have line breaks, replace .* with [\\s\\S]* .

Details

• ^ - start of string
• [az] - an ASCII letter
• \\d - a digit
• .* - any 0+ chars other than line break chars ( [\\s\\S] will match any chars).

NOTE : The .* (or [\\s\\S]* ) at the end are only a good idea if you need to use the match values. If not, when used with RegExp#test() , you may omit that part of the pattern.

Answer 2

You could just test the first two characters only.

 var cases = ['m1', 'm1a', 'M100bc', 's45', 'S396xyz', '', 'm', '1', '1a', 'mm', 'Mx', 'mm1', 'SS1']; console.log(cases.map(s => (/^[az]\\d/i.test(s))));