How do you sort a listBox by number value rather than alphabetically

[Nathan Revka]

I am storing card displays (eg J♣) in a list box through a list <KeyValuePair<string, int> and I want to order the cards numerically from greatest value to smallest value in the list box. When I change the sorting property on the properties box to "descending", the list is sorted inverse-alphabetically (ie Q is at top and 10 is at the bottom). I want to sort the list descending numerically, by value, so that A is at the top and 2 is at the bottom. How can I do this?

[Henry Minute]

Here is one way MSDN - ListBox.Sort Method[^]. Alternatively you can put your string and int into a class and implement the IComparable interface. Then, possibly, put them into a collection to add via the ListBox.DataSource property

Henry Minute Do not read medical books! You could die of a misprint. - Mark Twain Girl: (staring) "Why do you need an icy cucumber?" “I want to report a fraud. The government is lying to us all.”

[Moreno Airoldi]

You can implement a custom type for Cards and override the CompareTo() method to implement custom sorting. Something like:

    internal enum CardSuits
    {
        Spades = 0,
        Hearts,
        Diamonds,
        Clubs
    }

    internal enum CardValues
    {
        Two = 0,
        Three,
        Four,
        Five,
        Six,
        Seven,
        Eight,
        Nine,
        Ten,
        Jack,
        Queen,
        King,
        Ace
    }

    internal class Card : IComparable
    {
        internal CardSuits Suit;
        internal CardValues Value;

        internal Card(CardSuits Suit, CardValues Value)
        {
            this.Suit = Suit;
            this.Value = Value;
        }

        public int CompareTo(object obj)
        {
            int MyValue = (int)Value;
            Card OtherCard = (Card)obj;
            int OtherValue = (int)OtherCard.Value;
            return MyValue.CompareTo(OtherValue);
        }

        public override string ToString()
        {
            StringBuilder sb = new StringBuilder();
            switch (Value)
            {
                case CardValues.Two:
                    sb.Append("Two");
                    break;
                case CardValues.Three:
                    sb.Append("Three");
                    break;
                case CardValues.Four:
                    sb.Append("Four");
                    break;
                case CardValues.Five:
                    sb.Append("Five");
                    break;
                case CardValues.Six:
                    sb.Append("Six");
                    break;
                case CardValues.Seven:
                    sb.Append("Seven");
                    break;
                case CardValues.Eight:
                    sb.Append("Eight");
                    break;
                case CardValues.Nine:
                    sb.Append("Nine");
                    break;
                case CardValues.Ten:
                    sb.Append("Ten");
                    break;
                case CardValues.Jack:
                    sb.Append("Jack");
                    break;

[Luc Pattyn]

Hi, if your ListBox (or any other collection) contains items of type T, then you could provide an object implementing IComparer<T> and pass that to the Sort method. All that interface takes is providing a simple method int Compare(T x, T y) in which you can implement any sorting order you like. ------------------------------------------------------------------------------ FWIW: you can edit and delete your own messages if you need to. [EDIT] Sorry, the above is insufficient, ListBox.Sort() does not take any parameters. There are basically two ways of doing it: 1. implement your own sort method; e.g. a bubble sort where you compare two items (in any way you see fit) and swap them if necessary. 2. better way: use an intermediate collection, e.g. an array. This means: - ListBox.Items.CopyTo(array,0) copies the items into an array - ListBox.Items.Clear() removes the items - Array.Sort(array, IComparer) sorts the items - ListBox.Items.AddRange(array) adds them again, in the right order. [/EDIT] :)

Luc Pattyn [Forum Guidelines] [My Articles]

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modified on Saturday, August 8, 2009 3:46 PM