How to remove more than one dot (.) from text?

How to remove more than one dot (.) from text ?

for example:

123..45  =开发者_Go百科 123.45
10.20.30 = 10.2030
12.34    = 12.34
12..     = 12
123...45 = 123.45

how to do it ?

thanks in advance

It is not necessary to use regex, you can achieve what you need in this way:

 string s = "10.20.30";
        int n;
        if( (n=s.IndexOf('.')) != -1 )
            s = string.Concat(s.Substring(0,n+1),s.Substring(n+1).Replace(".",""));

Regex.Replace("Yourstring", "[.]{2,}",".");

Ok, using this overload of Regex.Replace, the trick here is to match everything after the first ., by using a look-behind group [ (?<= ] then to use a MatchEvaluator to clean that Match.

Regex.Replace(
    "127.0.8", //input string
    @"(?<=\.).*", //match everything after 1st "."
    m => m.Value.Replace(".",string.Empty)) //return value of match without "."

using System.Linq;
...
string s = "10.20.30";
while (s.Count( c => c == '.') > 1)
    s = s.Remove( s.LastIndexOf('.'),1);