private void btnOK_Click(object sender, EventArgs e) { if (ResultList.IsNotNull()) { List <string> list = new List <string>(); dgvList.EndEdit(); foreach (DataGridViewRow dr in dgvList.Rows) { DataGridViewCheckBoxCell checkCell = (DataGridViewCheckBoxCell)dr.Cells["dvCheck"]; if (Convert.ToBoolean(checkCell.Value) == true) { list.Add(dr.Cells["dvId"].Value.ToString()); } } CheckResultList = ResultList.FindAll(n => list.Exists(x => n.Id.IsEquals(x))); this.DialogResult = DialogResult.OK; } else { this.DialogResult = DialogResult.No; } }