Mi a hiba a kódban? (c#)

Gőzöm nincs a szálkezeléshezez is csak egy gyenge próbálkozás, de nem jó.

Ez a kód:

public partial class Form1 : Form

{

private Keys m_keys;

public Thread t1;

public Thread t2;

public Form1()

{

InitializeComponent();

timer1.Interval = 1;

timer1.Enabled = true;

timer1.Start();

}

private void Form1_KeyDown(object sender, KeyEventArgs e)

{

m_keys = e.KeyCode;

}

private void Form1_KeyUp(object sender, KeyEventArgs e)

{

m_keys = Keys.U;

}

public void ThreadFunction2()

{

try

{

MethodInvoker mi2 = new MethodInvoker(mozgas);

BeginInvoke(mi2);

}

catch

{

}

}

public void ThreadFunction()

{

try

{

MethodInvoker mi = new MethodInvoker(ugras);

BeginInvoke(mi);

}

catch

{

}

}

public void ugras()

{

if (m_keys == Keys.Up)

{

m_keys = Keys.U;

for (int i = 0; i < 50; i++)

{

pictureBox1.Location = new Point(pictureBox1.Location.X, pictureBox1.Location.Y - 5);

if (m_keys == Keys.Right)

{

pictureBox1.Location = new Point(pictureBox1.Location.X + 10, pictureBox1.Location.Y);

}

Thread.Sleep(2);

}

for (int i = 0; i < 50; i++)

{

pictureBox1.Location = new Point(pictureBox1.Location.X, pictureBox1.Location.Y + 5);

if (m_keys == Keys.Right)

{

pictureBox1.Location = new Point(pictureBox1.Location.X + 10, pictureBox1.Location.Y);

}

Thread.Sleep(2);

}

}

}

public void mozgas()

{

if (m_keys == Keys.Left)

{

pictureBox1.Location = new Point(pictureBox1.Location.X - 10, pictureBox1.Location.Y);

}

if (m_keys == Keys.Right)

{

pictureBox1.Location = new Point(pictureBox1.Location.X + 10, pictureBox1.Location.Y);

}

}

private void timer1_Tick(object sender, EventArgs e)

{

t2 = new Thread(new ThreadStart(ThreadFunction));

t2.IsBackground = true;

t2.Start();

t1 = new Thread(new ThreadStart(ThreadFunction2));

t1.IsBackground = true;

t1.Start();

}

Csak egy picturebox mozgatása jobbra balra egyik szálon ill. msásik szálon az "ugrás". De ugrás közbe mégse tudd jobbra vagy balra menni. Mit rontottam el a kódban?