开发者

Regex validation for numbers with comma separator

Need a regular expression to validate number with comma separator. 1,5,10,55 is valid but 1,,,,开发者_如何学Go10 is not valid.


This should do it:

^\d+(,\d+)*$

The regex is rather simple: \d+ is the first number, followed by optional commas and more numbers.

You may want to throw in \s* where you see fit, or remove all spaces before validation.

  • To allow negative numbers replace \d+ with [+-]?\d+
  • To allow fractions: replace \d+ with [+-]?\d+(?:\.\d+)?


Here are the components of the regex we're going to use:

  • \d is the shorthand for the digit character class
  • + is one-or-more repetition specifier
  • * is zero-or-more repetition specifier
  • (...) performs grouping
  • ^ and $ are the beginning and end of the line anchors respectively

We can now compose the regex we need:

^\d+(,\d+)*$

That is:

from beginning...
|    ...to the end
|          |
^\d+(,\d+)*$              i.e. ^num(,num)*$
 \_/  \_/ 
 num  num

Note that the * means that having just one number is allowed. If you insist on at least two numbers, then use + instead. You can also replace \d+ with another pattern for the number to allow e.g. sign and/or fractional part.

References

  • regular-expressions.info/Repetition, Character Classes, Grouping, Anchors

Advanced topics: optimization

Optionally you can make the brackets non-capturing for performance:

^\d+(?:,\d+)*$

And if the flavor supports it, you can make all repetition possessive in this case:

^\d++(?:,\d++)*+$

References

  • regular-expressions.info/Possessive


^[0-9]*(,){1}[0-9]*/

try this

0

上一篇:

下一篇:

精彩评论

暂无评论...
验证码 换一张
取 消

最新问答

问答排行榜