如何检查行是否存在？

Question

这是我在数据库表中显示/搜索记录的代码.如何判断是否存在roecord？它正在搜索成员的ID.如果记录不存在,我该如何显示消息？

 string connectionstring = "Server=Momal-PC\\MOMAL;Database=Project;Trusted_Connection=True;";
 SqlConnection conn = new SqlConnection();
 conn.ConnectionString = connectionstring;
 conn.Open();


  SqlDataAdapter sda = new SqlDataAdapter("Select * from Members where Number = '" + SearchID.Text + "'", conn);
  DataTable dtStock = new DataTable();

  sda.Fill(dtStock);
  dataGridView1.DataSource = dtStock;

  conn.Close();

Answer 1

if( 0 == dtStock.Rows.Count ) // does not exist