Private Sub Stretch(ByVal sender As Object, _
    ByVal e As EventArgs) Handles Button3.Click

    For Each column As DataGridViewImageColumn _
        In dataGridView1.Columns
        column.ImageLayout = DataGridViewImageCellLayout.Stretch
        column.Description = "Stretched image layout"
    Next
End Sub

Private Sub ZoomToImage(ByVal sender As Object, _
    ByVal e As EventArgs) Handles Button4.Click

    For Each column As DataGridViewImageColumn _
        In dataGridView1.Columns
        column.ImageLayout = DataGridViewImageCellLayout.Zoom
        column.Description = "Zoomed image layout"
    Next
End Sub

Private Sub NormalImage(ByVal sender As Object, _
    ByVal e As EventArgs) Handles Button5.Click

    For Each column As DataGridViewImageColumn _
        In dataGridView1.Columns
        column.ImageLayout = DataGridViewImageCellLayout.Normal
        column.Description = "Normal image layout"
    Next
End Sub

private void Stretch(object sender, EventArgs e)
{
    foreach (DataGridViewImageColumn column in
        dataGridView1.Columns)
    {
        column.ImageLayout = DataGridViewImageCellLayout.Stretch;
        column.Description = "Stretched";
    }
}

private void ZoomToImage(object sender, EventArgs e)
{

    foreach (DataGridViewImageColumn column in
        dataGridView1.Columns)
    {
        column.ImageLayout = DataGridViewImageCellLayout.Zoom;
        column.Description = "Zoomed";
    }
}

private void NormalImage(object sender, EventArgs e)
{

    foreach (DataGridViewImageColumn column in
        dataGridView1.Columns)
    {
        column.ImageLayout = DataGridViewImageCellLayout.Normal;
        column.Description = "Normal";
    }
}