private void autoSizeColumnsModeToolStripMenuItem_Click(object sender, EventArgs e)
{
ToolStripMenuItem control = (ToolStripMenuItem)sender;
foreach (ToolStripMenuItem item in autoSizeModeToolStripMenuItem.DropDownItems)
if (item != control)
item.Checked = false;
int index = (int)columnContextMenuStrip.Tag;
dataGridView1.Columns[index].AutoSizeMode = (DataGridViewAutoSizeColumnMode)Enum.Parse(typeof(DataGridViewAutoSizeColumnMode), (string)control.Tag);
}