OrderBy

In this chapter you will learn:

How to use OrderBy operator
How to sort string array by word length
Case-insensitive sort
Sort with custom Comparer

Get to know OrderBy operator

The following query emits a sequence of names in alphabetical order:

using System;/* j  a  v  a2s  .co  m*/
using System.Collections;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        string[] names = { "Java", "C#", "Javascript", "SQL", 
               "Oracle", "Python", "C++", "C", "HTML", "CSS" };

        IEnumerable<string> query = names.OrderBy(s => s);
        foreach(String s in query){
           Console.WriteLine(s);
        }
    }
}

The output:

Sort by word length

The following codesorts names by length.

using System;/*from   j  av a2s  .  c o  m*/
using System.Collections;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        string[] names = { "Java", "C#", "Javascript", "SQL", "Oracle", "Python", "C++", "C", "HTML", "CSS" };

        IEnumerable<string> query = names.OrderBy(s => s.Length);

        foreach(String s in query){
           Console.WriteLine(s);
        }
    }
}

The output:

Case-insensitive sort

The following code performs a case-insensitive sort:

using System;//  j  a v  a  2 s . c o m
using System.Collections;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        string[] names = { "Java", "C#", "Javascript", "SQL", "Oracle", "Python", "C++", "C", "HTML", "CSS" };

        names.OrderBy(n => n, StringComparer.CurrentCultureIgnoreCase);

        foreach (String s in names)
        {
           Console.WriteLine(s);
        }
    }
}

The output:

Sort with custom Comparer

using System;//from  j  av  a  2s . c o  m
using System.Collections.Generic;
using System.Linq;
using System.Text;

public class CaseInsensitiveComparer : IComparer<string> {
    public int Compare(string x, string y) {
        return string.Compare(x, y, true);
    }
}

public class MainClass {
    public static void Main() {

        string[] words = { "a", "A", "b", "B", "C", "c" };

        var sortedWords = words.OrderBy(a => a, new CaseInsensitiveComparer());


    }
}

Next chapter...

What you will learn in the next chapter:

How to use OrderByDescending operator