Question

I need to add a dash to a string, if there any characters after those digits, how would I do this with regex?

Examples:

dpa3455ad = dpa3455-ad

4545fd = 4545-fd

Answer 1

Use this regex: ( asssuming you want to add a dash at the first point of occurence of a non-digit after a set of digits)

(\d+)(\D.*)$

and replace with $1-$2

C# code:

Regex re = new Regex(@"(\d+)(\D.*)$");
Console.WriteLine(re.Replace("dpa3455ad", "$1-$2"));

Will give – dpa3455-ad

To keep it simple and insert a - at every occurence of a a non-digit following a digit, use this:

Regex re = new Regex(@"(\d)(\D)");
Console.WriteLine(re.Replace("dpa3455ad1s", "$1-$2"));

Will give – dpa3455-ad1-s