LINQ判断datagridview选中列是否有英文字母

int selcol = dataGridView1.CurrentCell.ColumnIndex;

var dr = from item in dtCopy.Columns[selcol].Table.Select()
where Regex.IsMatch(item.ItemArray[selcol].ToString(), @"[A-Za-z]")
select item;

if (dr.Count() == 0)//表示没有
{

}