Sorting a List> Uppercase and Lowercase

Question

var parameters = new List<KeyValuePair<string, string>>();
parameters.Add(new KeyValuePair<string, string>("AC", "123"));
parameters.Add(new KeyValuePair<string, string>("Ab", "123"));
parameters.Add(new KeyValuePair<string, string>("Db", "123"));
parameters.Add(new KeyValuePair<string, string>("CD", "123"));

var sortParameters = parameters.OrderBy(x => x.Key).ToList();

this is my source,

Result is

Ab
AC
CD
Db

but I need result

AC
Ab
CD
Db

sort by Uppercase and Lowercase.

How can I fix it.

This might help. Same Issue as yours. http://stackoverflow.com/a/13642177/3530469 — Kuriyama Mirai, Aug 28 '14 at 02:00

score 2 · Accepted Answer · answered Aug 28 '14 at 02:03

Here is the simple solution.

SortedDictionary<string, string> parameters = new SortedDictionary<string, string>(StringComparer.Ordinal);
        parameters.Add("AC", "123");
        parameters.Add("Ab", "123");
        parameters.Add("Db", "123");
        parameters.Add("CD", "123");

Enigmativity · Answer 2 · 2014-08-28T02:10:05.757

You can implement your own IComparer<string> to do the sort for you.

Try this:

public class StringByCharComparer : IComparer<string>
{
    public int Compare(string x, string y)
    {
        var xcs = x.ToCharArray();
        var ycs = y.ToCharArray();
        return Compare(xcs, ycs);
    }

    private int Compare(IEnumerable<char> xs, IEnumerable<char> ys)
    {
        if (!xs.Any() || !ys.Any())
        {
            return 0;
        }
        else
        {
            var x = xs.First();
            var y = ys.First();
            var r = x.CompareTo(y);
            if (r == 0)
            {
                r = Compare(xs.Skip(1), ys.Skip(1));
            }
            return r;
        }
    }
}

Then call it like so:

var sortParameters =
    parameters
        .OrderBy(x => x.Key, new StringByCharComparer())
        .ToList();

The results I get are:

Key    Value
AC     123 
Ab     123 
CD     123 
Db     123

I just learnt something from Seminda's answer.

You could just do this:

var sortParameters =
    parameters
        .OrderBy(x => x.Key, StringComparer.Ordinal)
        .ToList();

Simple.

Sorting a List> Uppercase and Lowercase

2 Answers2