Dim fr_bm As New Bitmap(Image.FromFile(AppDomain.CurrentDomain.BaseDirectory & "/images/u/image.gif"))
Dim to_bm As New Bitmap(16, 16)
Dim unitsimagearray(9) As Image
Dim gr As Graphics = Graphics.FromImage(to_bm)
For i As Integer = 0 To 9
    Dim fr_rect As New Rectangle(i * 19, 0, 16, 16) '0,19,38,76
    Dim to_rect As New Rectangle(0, 0, 16, 16)
    gr.DrawImage(fr_bm, to_rect, fr_rect, GraphicsUnit.Pixel)
    unitsimagearray(i) = to_bm
Next
u1.Image = unitsimagearray(0)

Private unitsimagearray(9) As Bitmap

Dim imagePath As String = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "/images/u/image.gif")
Dim picBoxes() As PictureBox = {u1, u2, u3, u4, u5, u6, u7, u8, u9, u10}

Using sourceBitmap As Bitmap = DirectCast(Image.FromFile(imagePath).Clone(), Bitmap)
    For i As Integer = 0 To 9
        Using sliceBitmap As Bitmap = New Bitmap(16, 16, PixelFormat.Format32bppArgb)
            Using g As Graphics = Graphics.FromImage(sliceBitmap)
                Dim sourceRect As New Rectangle(i * 19, 0, 16, 16)
                Dim destinationRect As New Rectangle(0, 0, 16, 16)
                g.DrawImage(sourceBitmap, destinationRect, sourceRect, GraphicsUnit.Pixel)
                unitsimagearray(i) = DirectCast(sliceBitmap.Clone(), Bitmap)
                picBoxes(i).Image = unitsimagearray(i)
            End Using
        End Using
    Next
End Using