C# Help: Sorting a List of Objects in C#

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Possible Duplicates:
Sort objects using predefined list of sorted values
C# Help: Sorting a List of Objects in C#

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Sorting a List of objects in C#

public class CarSpecs
{

    public CarSpecs()
    {
    }

    private String _CarName;
    public String CarName
    {
        get { return _CarName; }
        set { _CarName = value; }
    }



    private String _CarMaker;
    public String CarMaker
    {
       get { return _CarMaker;}
       set { _CarMaker = value; }
    }


    private DateTime _CreationDate;
    public DateTime CreationDate
    {
        get { return _CreationDate; }
        set { _CreationDate = value; }
    }
}

This is a list and I am trying to figure out an efficient way to sort this list List<CarSpecs> CarList, containing 6(or any integer amount) Cars, by the Car Make Date. I was going to do Bubble sort, but will that work? Any Help?

Thanks

Double post: http://stackoverflow.com/questions/925471/c-help-sorting-a-list-of-objects-in-c/925477#925477 — Noldorin, May 29 '09 at 11:33
Duplicate: http://stackoverflow.com/questions/925471/c-help-sorting-a-list-of-objects-in-c — Arjan Einbu, May 29 '09 at 11:33

score 42 · Answer 1 · answered May 29 '09 at 11:34

42

CarList = CarList.OrderBy( x => x.CreationDate ).ToList();

answered May 29 '09 at 11:34

Joel Coehoorn

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1

Coehoom what is x? is it lambda? how to define it? – Aditya Patil Jul 14 '14 at 07:27
1

@AdityaPatil x is a placeholder for individual items in the CarList sequence. `x => x.CreationDate` is an expression that tells the `OrderBy()` function what criteria to use for sorting the items. It means to sort by the CreationDate property of each item. – Joel Coehoorn Jul 14 '14 at 13:42
1

its technically called Lambda Expression right? – Aditya Patil Jul 15 '14 at 04:09

score 5 · Answer 2 · answered May 29 '09 at 11:37

First, using the shorthand syntax introduced in .Net 3.5, you could make this class definition a lot shorter:

public class CarSpecs
{
    public CarSpecs() { }

    public String CarName { get; set;
    public String CarMaker { get; set; }
    public DateTime CreationDate { get; set; }
}

This will compile into the exact same class as the one you have above.

Secondly, you can easily sort them using Lambda expressions or LINQ:

var linq = (from CarSpecs c in CarList
            orderby c.CreationDate ascending
            select c) as List<CarList>;

var lambda = CarList.OrderBy(c => c.CreationDate).ToList();

score 4 · Answer 3 · answered May 29 '09 at 11:36

Don't write your own sorting algorithm. .NET has an Array.Sort() method specifically for things such as this.

Since you have a custom object, you need to define how to compare 2 objects so the sorting algorithm knows how to sort them. You can do this 1 of 2 ways:

Make your CarSpecs class implement the IComparable interface
Create a class that implements IComparer and pass that in as a parameter to Array.Sort() along with your array.

score 0 · Answer 4 · answered May 29 '09 at 11:34

There are already existing sorting algorithms in the BCL - Array.Sort() and List.Sort(). Implement an IComparer class that determines the sort order using the CreationDate, then put all the objects into an array or list and call the appropriate Sort() method

C# Help: Sorting a List of Objects in C#

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