CSharp - Using custom comparer with OrderBy

Introduction

The IComparer<T> Interface is as follows:

interface IComparer<T> {
       int Compare(T x, T y);
}

IComparer interface requires us to implement a single method named Compare.

This method will accept two arguments of the same type T and will return an int that is

less than zero if the first argument is less than the second,
zero if the two arguments are equal, and
greater than zero if the second argument is greater than the first.

The following code created a class that implements the IComparer interface, which will order the elements based on their vowel-to-consonant ratios.

public class MyVowelToConsonantRatioComparer : IComparer<string>
{
    public int Compare(string s1, string s2)
    {
        int vCount1 = 0;
        int cCount1 = 0;
        int vCount2 = 0;
        int cCount2 = 0;

        GetVowelConsonantCount(s1, ref vCount1, ref cCount1);
        GetVowelConsonantCount(s2, ref vCount2, ref cCount2);

        double dRatio1 = (double)vCount1 / (double)cCount1;
        double dRatio2 = (double)vCount2 / (double)cCount2;

        if (dRatio1 < dRatio2)
            return (-1);
        else if (dRatio1 > dRatio2)
            return (1);
        else
            return (0);
    }

    public void GetVowelConsonantCount(string s,
                                       ref int vowelCount,
                                       ref int consonantCount)
    {

        string vowels = "AEIOU";
        vowelCount = 0;
        consonantCount = 0;
        string sUpper = s.ToUpper();

        foreach (char ch in sUpper)
        {
            if (vowels.IndexOf(ch) < 0)
                consonantCount++;
            else
                vowelCount++;
        }

        return;
    }
}

The class above contains two methods, Compare and GetVowelConsonantCount.

The Compare method is required by the IComparer interface.

The GetVowelConsonantCount method returns the number of vowels and consonants for a given input string.

Demo

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
class Program//from w w w . j a va 2  s.c  om
{
    static void Main(string[] args)
    {
        string[] codeNames = {
           "Python", "Java", "Javascript", "Bash", "C++", "Oracle"};

        MyVowelToConsonantRatioComparer myComp = new MyVowelToConsonantRatioComparer();

        IEnumerable<string> namesByVToCRatio = codeNames
          .OrderBy((s => s), myComp);

        foreach (string item in namesByVToCRatio)
        {
            int vCount = 0;
            int cCount = 0;

            myComp.GetVowelConsonantCount(item, ref vCount, ref cCount);
            double dRatio = (double)vCount / (double)cCount;

            Console.WriteLine(item + " - " + dRatio + " - " + vCount + ":" + cCount);
        }
    }
}
public class MyVowelToConsonantRatioComparer : IComparer<string>
{
    public int Compare(string s1, string s2)
    {
        int vCount1 = 0;
        int cCount1 = 0;
        int vCount2 = 0;
        int cCount2 = 0;

        GetVowelConsonantCount(s1, ref vCount1, ref cCount1);
        GetVowelConsonantCount(s2, ref vCount2, ref cCount2);

        double dRatio1 = (double)vCount1 / (double)cCount1;
        double dRatio2 = (double)vCount2 / (double)cCount2;

        if (dRatio1 < dRatio2)
            return (-1);
        else if (dRatio1 > dRatio2)
            return (1);
        else
            return (0);
    }

    public void GetVowelConsonantCount(string s,
                                       ref int vowelCount,
                                       ref int consonantCount)
    {

        string vowels = "AEIOU";
        vowelCount = 0;
        consonantCount = 0;
        string sUpper = s.ToUpper();

        foreach (char ch in sUpper)
        {
            if (vowels.IndexOf(ch) < 0)
                consonantCount++;
            else
                vowelCount++;
        }

        return;
    }
}

CSharp - Using custom comparer with OrderBy

Introduction

Demo

Result

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