How to return number of digits match between 2 strings

Question

I have 2 strings of same length. I need to know the number of digits the differ by.

string1: SH32OLP9843G, string2: SH12OLP9843G, Result: should be 1
string1: SH32OLP9843G, string2: SH12OLP0843G, Result: should be 2
string1: SH32OLP9843G, string2: SH12OLP08431, Result: should be 3
string1: SH32OLP9843G, string2: SH32OLP9843G, Result: should be 0

Im using this on SQL query like:

select * from sometable where fn_somefunction('string1',somefield) = 3
select * from sometable where someRegex between string1 and somefield = 1

Answer 1

Try following :

            string[,] inputs = {{"SH32OLP9843G", "SH12OLP9843G"},
                    {"SH32OLP9843G", "SH12OLP0843G"},
                    {"SH32OLP9843G", "SH12OLP08431"},
                    {"SH32OLP9843G", "SH32OLP9843G"}};

            for(int i = 0; i < inputs.GetLongLength(0); i ++)
            {
                char[] input1 = inputs[i, 0].ToCharArray();
                char[] input2 = inputs[i, 1].ToCharArray();

                int diff = input1.Select((x, index) => x == input2[index] ? 0 : 1).Sum();
            }