Sort array of objects in C#

Question

i want to sort the array joblist by job_number property.can anyone tell me way to do it. i try to use deletage but gives error like this

Run-time exception (line 160): Failed to compare two elements in the array.

Stack Trace:

[System.NullReferenceException: Object reference not set to an instance of an object.] at RushJob.b__0(RushJob r1, RushJob r2):line 162 at System.Array.FunctorComparer 1.Compare(T x, T y) at System.Collections.Generic.ArraySortHelper 1.InsertionSort(T[] keys, Int32 lo, Int32 hi, IComparer 1 comparer) at System.Collections.Generic.ArraySortHelper 1.IntroSort(T[] keys, Int32 lo, Int32 hi, Int32 depthLimit, IComparer 1 comparer) at System.Collections.Generic.ArraySortHelper 1.IntrospectiveSort(T[] keys, Int32 left, Int32 length, IComparer 1 comparer) at System.Collections.Generic.ArraySortHelper 1.Sort(T[] keys, Int32 index, Int32 length, IComparer`1 comparer)

[System.InvalidOperationException: Failed to compare two elements in the array.] at System.Collections.Generic.ArraySortHelper 1.Sort(T[] keys, Int32 index, Int32 length, IComparer 1 comparer) at System.Array.Sort[T](T[] array, Int32 index, Int32 length, IComparer 1 comparer) at System.Array.Sort[T](T[] array, IComparer 1 comparer) at System.Array.Sort[T](T[] array, Comparison`1 comparison) at RushJob.Main(String[] args):line 160

using System;


public class Job
{
    private int _job_number;
    private string _customer_name;
    private string _job_description;
    private int _estimated_hour;
    protected int _price;

    public Job(int job_number, string c_name, string j_des, int e_hour)
    {
        _job_number = job_number;
        _customer_name = c_name;
        _job_description = j_des;
        _estimated_hour = e_hour;
        _price = e_hour * 45;

    }

    

    public int job_number
    {
        get
        {
            return _job_number;
        }
        set
        {
            _job_number = value;
        }

    }

    public string job_description
    {
        get
        {
            return _job_description;

        }
        set
        {
            _job_description = value;
        }

    }

    public string customer_name
    {
        get
        {
            return _customer_name;

        }
        set
        {
            _customer_name = value;
        }

    }
    public int get_price()
    {

        return _price;

    }

    public bool Equals(Job j)
    {
        if (j._job_number == this._job_number)
        {
            return true;
        }
        else
        {
            return false;
        }

    }

    public override int GetHashCode()
    {
        return this._job_number;
    }

    public override string ToString()
    {
        return "Job Number: " + _job_number + " Customer name: " + _customer_name + " Job Description: " + _job_description + " Estimated Hours: " + _estimated_hour + " Price: " + _price;
    }

}

public class RushJob : Job
{
    public RushJob(int job_number, string c_name, string j_des, int e_hour) : base(job_number, c_name, j_des, e_hour)
    {
        this._price += 150;
    }
    

    


    public static void Main(string[] args)
    {
        RushJob[] joblist = new RushJob[5];
        int job_number;
        string customer_name;
        string job_description;
        int estimated_hour;


        bool take_input = true;
        int index = 0;
        while (take_input)
        {
            Console.WriteLine("Enter Job Number");
            job_number = int.Parse(Console.ReadLine());
            int duplicate = 0;
            for (int i = 0; i < index; i++)
            {
                if (joblist[i].job_number == job_number)
                {
                    Console.WriteLine("Job Already Exists.Please Enter a new job");
                    duplicate = 1;
                    break;
                }
            }
            if (duplicate == 1)
            {
                continue;
            }

            if (duplicate == 0)
            {
                Console.WriteLine("Enter Customer Name");
                customer_name = Console.ReadLine();
                Console.WriteLine("Enter Job Description");
                job_description = Console.ReadLine();
                Console.WriteLine("Enter Estimated Hour");
                estimated_hour = int.Parse(Console.ReadLine());
                joblist[index] = new RushJob(job_number, customer_name, job_description, estimated_hour);
                Console.WriteLine("Job Added Successfully\n\n");
                index++;
            }
            if (index == 2)
            {
                Console.WriteLine("Five Jobs Added Successfully\n\n");
                take_input = false;
            }


        }
        int total_price = 0;
        //Comparison<RushJob> comparison = (x, y) => x.job_number.CompareTo(y.job_number);
        //joblist = Array.Sort(joblist,new comparison());
        Array.Sort(joblist, delegate (RushJob r1, RushJob r2)
         {
             return r1.job_number.CompareTo(r2.job_number);
         });
        for (int i = 0; i < joblist.Length; i++)
        {
            Console.WriteLine(joblist[i].ToString());
            total_price += joblist[i].get_price();
        }
        Console.WriteLine(total_price);
    }
}

Answer 1

using System.Linq;
public static void Main(string[] args)
{
    var joblist = new List<RushJob>();
    int job_number;
    string customer_name;
    string job_description;
    int estimated_hour;

    bool take_input = true;
    int index = 0;
    while (take_input)
    {
        Console.WriteLine("Enter Job Number");
        var sJobNumber = Console.ReadLine();
        if (string.IsNullOrEmpty(sJobNumber))
            break;
        job_number = int.Parse(sJobNumber);
        if (joblist.Any(j => j.job_number == job_number))
        {
            Console.WriteLine("Job Already Exists. Please Enter a new job");
        }
        else
        {
            Console.WriteLine("Enter Customer Name");
            customer_name = Console.ReadLine();
            Console.WriteLine("Enter Job Description");
            job_description = Console.ReadLine();
            Console.WriteLine("Enter Estimated Hour");
            estimated_hour = int.Parse(Console.ReadLine());
            var job = new RushJob(job_number, customer_name, job_description, estimated_hour);
            joblist.Add(job);
            Console.WriteLine("Job Added Successfully\n\n");
            index++;
        }
    }
    joblist.Sort(delegate (RushJob r1, RushJob r2)
    {
        return r1.job_number.CompareTo(r2.job_number);
    });
    foreach(var job in joblist)
    { 
        Console.WriteLine(job.ToString());
    }
    var total_price = joblist.Sum(j => j.get_price());
    Console.WriteLine(total_price);
}