Regex - only allow single spaces within a string

Question

I need to restrict a string to only allow letters, numbers, hyphens, ampersands, apostrophes and single spaces.

From a bit of searching I've got this so far:

^[A-Za-z0-9-'&\s]{1,}$

But this allows for double spaces. How do I write the regular expression so that it only allows single spaces (there might not be any at all)?

Damien_The_Unbeliever · Accepted Answer · 2013-08-09 10:51:52Z

7

Match any of the other allowed values, followed by an optional single space:

^\s?([A-Za-z0-9-'&]\s?){1,}$

(I also added an optional one at the start, if that's allowed)

answered Aug 9, 2013 at 10:51

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Comments

Sergey K · Accepted Answer · 2013-08-09 10:56:34Z

1

Try this
^([A-Za-z0-9-'&]+\s?)+$

answered Aug 9, 2013 at 10:56

Sergey K

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MayankGaur · Accepted Answer · 2019-11-15 04:58:35Z

0

I have tried with different scenario it works fine with me ^\b(?!.*?\s{2})[A-Za-z0-9 ]{1,50}\b$

[RegularExpression(@"^\b(?!.*?\s{2})[A-Za-z0-9 ]{1,50}\b$", ErrorMessage ="String is not valid"]
public string FirstName{ get; set; }

answered Nov 15, 2019 at 4:58

MayankGaur

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