[Help]PictureBox Frame [Solved]

Bitmap bitmap = (Bitmap)pictureBox.Image;

for (int x = 0; x < bitmap.Width; x += 1) // horizontal lines
{
     bitmap.SetPixel(x, 0, Color.Red); // top line
     bitmap.SetPixel(x, bitmap.Height - 1, Color.Red); // bottom line
}
for (int y = 0; y < bitmap.Height; y += 1) // vertical lines
{
     bitmap.SetPixel(0, y, Color.Red); // left line
     bitmap.SetPixel(bitmap.Width - 1, y, Color.Red); // right line
}

pictureBox.Image = (Image)bitmap;

Dim bitmap As Bitmap = DirectCast(pictureBox.Image, Bitmap)
For x As Integer = 0 To bitmap.Width - 1
    ' horizontal lines
    bitmap.SetPixel(x, 0, Color.Red)
    ' top line
        ' bottom line
    bitmap.SetPixel(x, bitmap.Height - 1, Color.Red)
Next
For y As Integer = 0 To bitmap.Height - 1
    ' vertical lines
    bitmap.SetPixel(0, y, Color.Red)
    ' left line
        ' right line
    bitmap.SetPixel(bitmap.Width - 1, y, Color.Red)
Next
pictureBox.Image = DirectCast(bitmap, Image)