Clear image on picturebox

Question

How can I clear draw image on picturebox? The following doesn't help me:

pictbox.Image = null;
pictbox.Invalidate();

Please help.

EDIT

private void pictbox_Paint(object sender, PaintEventArgs e) 
{ 
     Graphics g = e.Graphics; 
     vl.Draw(g, ref tran.realListForInsert); 
} 

public void Draw(Graphics g, ref List<double> arr) 
{ 
    g.DrawRectangle(new Pen(Brushes.Red, 3), nodeArr[Convert.ToInt32(templstName)].pict.Location.X, nodeArr[Convert.ToInt32(templstName)].pict.Location.Y, 25, 25); 
    g.DrawRectangle(new Pen(Brushes.Green, 3), nodeArr[Convert.ToInt32(templstArgName)].pict.Location.X, nodeArr[Convert.ToInt32(templstArgName)].pict.Location.Y, 25, 25); 
    nodeArr[Convert.ToInt32(templstName)].text.Text = arr[Convert.ToInt32(templstArgName)].ToString(); 
    arr[Convert.ToInt32(templstName)] = arr[Convert.ToInt32(templstArgName)]; 
} 

Answer 1

Its so simple! You can go with your button click event, I used it with a button property Name: "btnClearImage"

// Note 1a:
// after clearing the picture box 
// you can also disable clear button 
// by inserting follwoing one line of code:

btnClearImage.Enabled = false   

// Note 1b:
// you should set your button Enabled property
// to "False"
// after that you will need to Insert 
// the following line to concerned event or button
// that load your image into picturebox1 
// code line is as follows:

btnClearImage.Enabled = true;

Answer 2

You should try. When you clear your Graphics you must choose color. SystemColors.Control is native color of form

Graphics g = pB.CreateGraphics();
g.Clear(SystemColors.Control);

Answer 3

if (pictureBox1.Image != null)
{
    pictureBox1.Image.Dispose();
    pictureBox1.Image = null;
}

Answer 4

private void ClearBtn_Click(object sender, EventArgs e)
{
    Studentpicture.Image = null;
}

Answer 5

As others have said, setting the Image property to null should work.

If it doesn't, it might mean that you used the InitialImage property to display your image. If that's indeed the case, try setting that property to null instead:

pictBox.InitialImage = null;