下面是一段数据库的访问代码,获取表student 中记录条数,并在屏幕上输出。请填写完整 。 static void Main(string[] args) { string str="Integrated Security=SSPI; database=Test; server=localhost\\sqlexpress;"; SqlConnection conn = new SqlConnection(); (1) ; SqlCommand cmd = new SqlCommand(); cmd.Connection = conn ; cmd.CommandType = CommandType.Text; cmd.CommandText = "select count(*) from student "; (2) ; Console.WriteLine( (3) ); (4) ; }