javascript - AngularJs ng-pattern regex - Stack Overflow

admin管理员组

文章数量:1356304

I am struggling writing a Regex for angular ng-pattern to validate a form input field.An example of the possible inputs are below

Valid input:

@tag1,@tag2,@tag3
@tag1, @tag2, @tag3
@tag1

Invalid Input:

@tag 1
@tag 1, @tag2, @tag  -3
@ta g1, @t ag2

Basically it should allow ma and ma whitespace, but not allow whitespace in between tags.

I have written a REGEX that matches all the invalid input, but when I use this in ng-pattern it does not do the correct validation.

Regex Built: /((^, @|@\s+)|@*[a-zA-Z0-9]* +[a-zA-Z0-9])/g Link:

Any help is much appreciated!

I am struggling writing a Regex for angular ng-pattern to validate a form input field.An example of the possible inputs are below

Valid input:

@tag1,@tag2,@tag3
@tag1, @tag2, @tag3
@tag1

Invalid Input:

@tag 1
@tag 1, @tag2, @tag  -3
@ta g1, @t ag2

Basically it should allow ma and ma whitespace, but not allow whitespace in between tags.

I have written a REGEX that matches all the invalid input, but when I use this in ng-pattern it does not do the correct validation.

Regex Built: /((^, @|@\s+)|@*[a-zA-Z0-9]* +[a-zA-Z0-9])/g Link: https://regex101./r/HMVdLD/1

Any help is much appreciated!

• javascript
• angularjs
• regex
• ng-pattern

Share Improve this question Follow asked Apr 13, 2017 at 12:35 Steven.linSteven.lin 11111 gold badge44 silver badges1111 bronze badges 3

• 3 Why use a regex that matches invalid input? – Wiktor Stribiżew Commented Apr 13, 2017 at 12:37
• I tried negating the above expression. That does not seem to work either. – Steven.lin Commented Apr 13, 2017 at 12:41
• 2 Look, /^@[a-zA-Z0-9]+(?:,\s*@[a-zA-Z0-9]+)*$/ should match all valid ones, and it is much easier. Put it into the ng-pattern attribute value (ng-pattern="/pattern/"). What about leading/trailing whitespace? Do you want it to be allowed in your input field? – Wiktor Stribiżew Commented Apr 13, 2017 at 12:44

Add a ment  | 

1 Answer 1

Sorted by: Reset to default 6

I suggest defining a pattern to match valid inputs, like

ng-pattern="/^@[a-zA-Z0-9]+(?:,\s*@[a-zA-Z0-9]+)*$/"

See the regex demo

If you want to disallow leading and trailing whitespace, add ng-trim="false".

Pattern details:

• ^ - start of string
• @ - a literal @ symbol
• [a-zA-Z0-9]+ - 1+ alphanumerics
• (?:,\s*@[a-zA-Z0-9]+)* - 0+ sequences of:
  • , - ma
  • \s* - 0+ whitespaces
  • @[a-zA-Z0-9]+ - same as above
• $ - end of string.

本文标签： javascriptAngularJs ngpattern regexStack Overflow