>Ok, something's wrong.
>
>When I do this:
>
>

>public partial class Form1 : Form
>{
>    public Form1()
>    {
>        InitializeComponent();
>    }
>
>    protected override void OnPaint(PaintEventArgs e)
>    {
>        new DeckOfCards().DrawACard(e.Graphics.GetHdc(), 10, 10, 21, 1, 255);
>    }
>}
>

>
>I get a big red X the size of the form with a red border around it.
>
>When I do this:
>
>

>public partial class Form1 : Form
>{
>    DeckOfCards Deck = null;
>
>    public Form1()
>    {
>        InitializeComponent();
>        Deck = new DeckOfCards();
>    }
>
>    protected override void OnPaint(PaintEventArgs e)
>    {
>        Deck.DrawACard(e.Graphics.GetHdc(), 10, 10, 21, 1, 255);
>    }
>}
>

>
>I get an exception in Deck's CTOR "Unable to find an entry point named 'cdtInit' in DLL 'cards.dll'.".
>
>Any idea what's wrong?

Sounds like it's finding a Cards.dll that is not the standard one. Any cards.dll files other than in the System32 folder?
You could try supplying the full path in the DLLImport[]....
Don't know what OS you're on but on mine at the moment (XP) System32/Cards.dll is v5.1.2600.0


>
>
>
>
>
>
>>>I thought I'd try to use the Cards.Dll that ships with Windows to draw a card on a C# WinF/orm.
>>>
>>>The Object Explorer shows this method in Cards.DLL:
>>>
>>>

>>>cards.cardsdll.drawcard(System.IntPtr, int, int, int, int, int)
>>>

>>>
>>>So I wrote this:
>>>
>>>

>>>public class DeckOfCards
>>>{
>>>    [DllImport("cards.dll")]
>>>    private static extern bool drawcard(ref IntPtr handle, ref int top, ref int left, 
>>>           ref int width, ref int height, ref int card);
>>>
>>>    public DeckOfCards()
>>>    {
>>>    }
>>>
>>>    public bool DrawACard(IntPtr canvas, int top, int left, int width, int height, int card)
>>>    {
>>>        return drawcard(ref canvas, ref top, ref left, ref height, ref width, ref card);
>>>    }
>>>}
>>>

>>>
>>>Then I attempted to use it like this:
>>>
>>>

>>>public partial class Form1 : Form
>>>{
>>>    public Form1()
>>>    {
>>>        InitializeComponent();
>>>
>>>            DrawCard();
>>>    }
>>>
>>>    private void DrawCard()
>>>    {
>>>        DeckOfCards Deck = new DeckOfCards();
>>>
>>>        IntPtr hdc = this.Handle;
>>>
>>>        Deck.DrawACard(hdc, 10, 10, 100, 50, (int)Ranks.Five * 4 + (int)Suits.Clubs);
>>>
>>>    }
>>>}
>>>

>>>
>>>It dies in the DrawACard method of my class with "Unable to find an entry point named 'drawcard' in DLL "cards.dll'.
>>>
>>>As I have little to no experience working with COM in .Net (yet) I'm hoping someone can see what's wrong.
>>
>>I don't think cards.dll has that method. Based on some old stuff I found try something like this:

    public class DeckOfCards
>>    {
>>        [DllImport("cards.dll")]
>>        private static extern bool cdtInit(ref int width, ref int height);
>>
>>        [DllImport("cards.dll")]
>>        private static extern bool cdtDraw(IntPtr hdc, int x, int y, int card, int mode, long color);
>>        
>>        public DeckOfCards()
>>        {
>>            int width = 150; int height = 150;
>>            if (!cdtInit(ref width, ref height))
>>                throw new Exception("Could not initialize");
>>        }
>> 
>>        public bool DrawACard(IntPtr canvas, int left, int top, int card, int mode, long color)
>>        {
>>           return  cdtDraw(canvas, left, top,card, mode, color);
>>        }
>>    }

Also I don't think you can draw it using the handle. Try from the forms OnPaint():

new DeckOfCards().DrawACard(e.Graphics.GetHdc(), 10, 10, 16 ,1,207);

Of course in reality you wouldn't create an instance of DeckOfCards every time - just keep one hanging around somewhere.....