C# Regex - Accept spaces in a string

Question

I have an application which needs some verifications for some fields. One of them is for a last name which can be composed of 2 words. In my regex, I have to accept these spaces so I tried a lot of things but I did'nt find any solution. Here is my regex : ``` @"^[a-zA-Zàéèêçñ\s][a-zA-Zàéèêçñ-\s]+$" ``` The `\s` are normally for the spaces but it does not work and I got this error message : ``` parsing "^[a-zA-Zàéèêçñ\s][a-zA-Zàéèêçñ-\s]+$" - Cannot include class \s in character range. ``` ANy idea guys?

Accepted Answer

`-` denotes a character range, just as you use `A-Z` to describe any character between A and Z. Your regex uses `ñ-\s` which the engine tries to interpret as any character between ñ and \s -- and then notices, that `\s` doesn't make a whole lot of sense there, because `\s` itself is only an abbreviation for any whitespace character.

That's where the error comes from.

To get rid of this, you should always put `-` at the end of your character class, if you want to include the `-` literal character:

```
@"^[a-zA-Zàéèêçñ\s][a-zA-Zàéèêçñ\s-]+$"
```

This way, the engine knows that `\s-` is not a character range, but the two characters `\s` and `-` seperately.

The other way is to escape the `-` character:

```
@"^[a-zA-Zàéèêçñ\s][a-zA-Zàéèêç\-\s]+$"
```

So now the engine interprets `ñ\-\s` not as a character range, but as any of the characters `ñ`, `-` or `\s`. Personally, though I always try to avoid escaping as often as possible, because IMHO it clutters up and needlessly stretches the expression in length.

C# Regex - Accept spaces in a string

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