正则表达式，仅将名称与一个空格匹配

Question

I have a string condition in js where i have to check whether name entered in text box contains with one space only.

 pattern: name.status === 'full_name' ? /^[a-zA-Z.+-.']+\s+[a-zA-Z.+-. ']+$/ : /^[a-zA-Z.+-. ']+$/

But the above regex matches names ending with 2 spaces also.

I need to match it such that the entered name should accept only one space for a name string. So the name will have only one space in between or at the end.

Answer 1

Two observations: 1) \\s+ in your pattern matches 1 or more whitespaces, and 2) [+-.] matches 4 chars: + , , , - and . , it is thus best to put the hyphen at the end of the character class.

You may use

/^[a-zA-Z.+'-]+(?:\s[a-zA-Z.+'-]+)*\s?$/

See the regex demo

Details

• ^ - start of string
• [a-zA-Z.+'-]+ - 1 or more letters, . , + , ' or -
• (?:\\s[a-zA-Z.+'-]+)* - zero or more sequences of:
  • \\s - a single whitespace
  • [a-zA-Z.+'-]+ - 1 or more letters, . , + , ' or - chars
• \\s? - an optional whitespace
• $ - end of string.

Note: if the "names" cannot contain . and + , just remove these symbols from your character classes.

Answer 2

/^\S+\s\S+$/

try this

Some explanations:

• ^ - start of string
• \\s - single whitespace
• \\S - everything except whitespace
• "+"- quantifier "one or more"
• $ - end of string

Answer 3

you could also use word boundaries...

 function isFullName(s) { return /^\\b\\w+\\b \\b\\w+\\b$/.test(s); } ['Giuseppe', 'Mandato', 'Giuseppe Mandato'] .forEach(item => console.log(`isFullName ${item} ? ${isFullName(item)}`))