[bo]存储过程[/bo] CREATE PROCEDURE pd_name @userName char,@userPass int ,@m  int output
as select m=count(*)  from name where 用户名=@userName and 密码=@userPass
GO
[bo]C#[/bo]
SqlConnection conn = new SqlConnection("server=localhost;uid=sa;pwd=s;database=s");
            SqlCommand cmd = new SqlCommand("pd_name", conn);
             = CommandType.StoredProcedure;
            cmd.Parameters.Add("@userName", SqlDbType.Char, 20);
            cmd.Parameters["@userName"].Value = textBox1.Text;
            cmd.Parameters.Add("@userPass", SqlDbType.Int, 4);
            cmd.Parameters["@userPass"].Value = textBox2.Text;
            cmd.Parameters.Add("@m", SqlDbType.Int, 4);
            cmd.Parameters["@m"].Direction = ParameterDirection.Output;
                    conn.Open();
                    int val = 1;                                 
                 int val=cmd.ExecuteNonQuery();接收不到值
                    conn.Close();      
                  if (val==1)
                      form1.Show();   
                    else
                        MessageBox.Show("帐号或密码错误");

解决了 数据库返回值未定义