Question

I have a string1, string2,...,stringn
and values of each strings are

string1 = "s1k1-s1k2-s1k3-....-s1kn | s1v1-s1v2-s1v3-....-s1vn";

string2 = "s2k1-s2k2-s2k3-....-s2kn | s2v1-s2v2-s2v3-....-s2vn";

                .............

stringn = "snk1-snk2-snk3-....-snkn | snv1-snv2-snv3-....-snvn";

Now, I want to populate the Dictionary<string, string>() with the key and values as follows.

var dict = new Dictionary<string, string>();
dict.Add(s1k1, s1v1);
dict.Add(s1k2, s1v2);
         :
         :
dict.Add(snkn, snvn);

Below is my sample code:

        string string1 = "s1k1-s1k2-s1k3-s1kn|s1v1-s1v2-s1v3-s1vn";
        string string2 = "s2k1-s2k2-s2k3-s2kn|s2v1-s2v2-s2v3-s2vn";
        string stringn = "snk1-snk2-snk3-snkn|snv1-snv2-snv3-snvn";

        var dict = new Dictionary<string, string>();

        new List<string> { string1, string2, stringn }.ForEach(str =>
        {
            var strSplit = str.Split('|');
            var strKeys = strSplit[0].Split('-');
            var strValues = strSplit[1].Split('-');
            strKeys.Zip(strValues, (key, value) => new { key, value }).ToList().ForEach(filed => dict.Add(filed.key, filed.value));
        });

Is it possible to optimize this code ?

Answer 1

To my mind the most costly operation here in terms of memory usage is strSplit = str.Split('|'). It creates two large strings that go directly to a garbage after strKeys and strValues are obtained. Later all these garbage strings will be collected by garbage collector which will negatively affect the performance.

The strKeys and strValues string arrays contain strings that will be used in dict, so the memory loss here is minimal.

To optimize memory usage you’ll have to traverse str char-by-char and create keys and values using StringBuilder class. In this case memory loss will be minimal, however your code won’t be as clean as it is now. So I would recommend such solution only if this part of the code is the real performance bottleneck in your application.