Question

I need a method to check if a string contains one or more similar characters to another. I dont want to find all strings containing the letter “D”.
For example, if I have a string “Christopher” and want to see if “Chris” is contained in “Christopher”, I want that to return. However, if I want to see if “Candy” is in the string “Christopher”, I wont want it to return just because it has a “C” in common.

I have tried the .Contains() method but cant give that rules for 2 or more similar characters and I have thought about using regular expressions but that might be a bit over kill. The similar letters must be next to eachother.

Thank you 🙂

Answer 1

This looks for each 2-character-gram of s1 and looks for it in s2.

string s1 = "Chrx";
string s2 = "Christopher";
IsMatchOn2Characters(s1, s2);

static bool IsMatchOn2Characters(string a, string b)
{
    string s1 = a.ToLowerInvariant();
    string s2 = b.ToLowerInvariant();

    for (int i = 0; i < s1.Length - 1; i++)
    {
       if (s2.IndexOf(s1.Substring(i,2)) >= 0)
          return true; // match
    }

    return false; // no match
}