C#

int dll_registerAccount(char* uri, char* reguri, char*);

[DllImport("pjsipDlld")]
static extern int dll_registerAccount(IntPtr uri, 
                                      IntPtr reguri);

success = dll_registerAccount("Bob", "Joe");

bool signalled = autoResetEvent.GetActionServerEvent.WaitOne();
if (!signalled)
   return "time out";
else
{
//code here
}

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
        SetStyle(ControlStyles.AllPaintingInWmPaint, true);
        SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        try
        {
            Card cTest = new Card();
            cTest.Location = new Point(5, 5);
            cTest.CardFace = Properties.Resources.AceClub;
            Controls.Add(cTest);

            Card cTest2 = new Card();
            cTest2.Location = new Point(50, 5);
            cTest2.CardFace = Properties.Resources.AceClub;
            Controls.Add(cTest2);
        }
        catch (Exception Ex)
        {
            MessageBox.Show(Ex.Message);
        }
    }
}

public partial class Card : UserControl
{
    Bitmap _CardFace;
    Boolean _bMouseDown = false;
    Point _pMouse;

    public Bitmap CardFace
    {
        get { return _CardFace; }
        set
        {
            _CardFace = value;
            Width = _CardFace.Width;
            Height = _CardFace.Height;
        }
    }

    public Card()
    {
        InitializeComponent();
        SetStyle(ControlStyles.SupportsTransparentBackColor, true);
        SetStyle(ControlStyles.Opaque, true);
        BackColor = Color.Transparent;
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        Graphics gGraphics = e.Graphics;
        gGraphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
        gGraphics.DrawImage(CardFace, new Point(0, 0));
    }

    protected override void OnPaintBackground(PaintEventArgs e)
    {
        //base.OnPaintBackground(e);
    }

    protected override void OnMouseDown(MouseEventArgs e)
    {
        _bMouseDown = true;
        _pMouse = e.Location;
        BringToFront();
    }

    protected override void OnMouseUp(MouseEventArgs e)
    {
        _bMouseDown = false;
    }

    protected override void OnMouseMove(MouseEventArgs e)
    {
        if (Capture && _bMouseDown)
        {
            Point P2CP = Parent.PointToClient(Cursor.Position);
            Location = new Point(P2CP.X - _pMouse.X, P2CP.Y - _pMouse.Y);
        }
    }
}

using System;

class Drivers_License_Exam
    {
        static void Main()
        {
            char[] exArray = new char[] { 'B', 'D', 'A', 'A', 'C', 'A', 'B', 'A', 'C', 'D', 'B', 'C', 'D', 'A', 'D', 'C', 'C', 'B', 'D', 'A' };
            char[] userArray = new char[20];
            char ansHold;
            char[] correct = new char[20];
            //int correct = 0;

            //GET USER'S ANSWERS AND CONVERT TO UPPERCASE

            for (int i = 0; i < userArray.Length; i++)
            {
                Console.Write("Question #{0}: ", (i + 1));
                ansHold = Convert.ToChar(Console.ReadLine());
                ansHold = Char.ToUpper(ansHold);

                while (ansHold < 'A' || ansHold > 'D')
                {
                    Console.WriteLine("Invalid answer, please enter a letter A through D");
                    Console.Write("Question #{0}: ", (i + 1));
                    ansHold = Convert.ToChar(Console.ReadLine());
                    ansHold = Char.ToUpper(ansHold);

                }
                userArray[i] = ansHold; 
            }
            
            TotalCorrect(correct); 
        }
            public static void TotalCorrect(char[] userAnswers)
            {
                char[] examAnswers = new char[] { 'B', 'D', 'A', 'A', 'C', 'A', 'B', 'A', 'C', 'D', 'B', 'C', 'D', 'A', 'D', 'C', 'C', 'B', 'D', 'A' }; 
                int[] wrongAnswers = new int[20];
                int j = 0; 
                int countCorrect = 0;


                for (int i = 0; i < 20; i++)
                {
                    if (userAnswers[i] == examAnswers[i])
                    {
                        countCorrect += 1;
                    }
                    else // wrong answer
                    {
                        wrongAnswers[j] = i + 1;
                        j++;
                    }
                    
                }
                Console.WriteLine("");
                Console.WriteLine("There are {0} correct answer(s).", countCorrect);
            }
    }