Question

Basically I want to retrieve all possible substring matches with n characters from a string, Here’s my initial code but it only returns 2 matches.

String input = "abc12345abcd";
Regex  regex = new Regex(@"[A-Za-z]{3}"); //this will only return 2 matches
MatchCollection  matches = regex.Matches(input);

How should I get the following matches using regex?

abc
abc
bcd

Is this possible, if not will LINQ help this?

Answer 1

String input = "abc12345abcd";
Regex regex = new Regex(@"[A-Za-z]{3}");
int i=0;
while(i<input.Length){
    Match m=regex.Match(input,i);
    if(m.Success){
        Console.WriteLine(m.Value);
        i=m.Index+1; //just increment one char, instead of length of match string
    }else break;
}

Results

abc
abc
bcd