c# winform datagridview 显示行号

长时间不写，就忘了，备忘一下

dataGridView1.RowHeadersVisible = true;
dataGridView1.RowHeadersWidth = 150;
dataGridView1.RowStateChanged += (s, args) =>
{
    args.Row.HeaderCell.Value = string.Format("{0}", args.Row.Index + 1);
};