C and asp. net link database parameters in several method instance code

#region  Parameter passing method no 1 Kind of 
     // Parameter setting method (s) 1 A) 
     //SqlParameter sp = new SqlParameter("@Name", str_Name);
     //SqlParameter sp2 = new SqlParameter("@Pwd", str_Pwd);
     //cmd.Parameters.Add(sp);
     //cmd.Parameters.Add(sp2);
 #endregion
// simple 1 Use the first 1 Kind of 
#region  The number of parameters passed 2 methods ( Is the first 1 The omission of a species passes on a variable )
    cmd.Parameters.Add(new SqlParameter("@Name", str_Name));
    cmd.Parameters.Add(new SqlParameter("@Pwd", str_Pwd));
   #endregion
#region  The number of parameters passed 3 A method (array passing) 
  //SqlParameter[] sp = new SqlParameter[] { new SqlParameter("@Name", str_Name), new SqlParameter("@Pwd", str_Pwd) };
  //cmd.Parameters.AddRange(sp);
#endregion
#region  The number of parameters passed 4 methods (AddWithValue)
 //cmd.Parameters.AddWithValue("@Name", str_Name);
 //cmd.Parameters.AddWithValue("@Pwd", str_Pwd);
#endregion
// A large project 1 Use the first 5 Kind of 
#region  The number of parameters passed 5 methods ( With the first 1 Similarly, increase the database parameter type )
   //SqlParameter sps = new SqlParameter("@Name", SqlDbType.NVarChar);
   //SqlParameter sps2 = new SqlParameter("@Pwd", SqlDbType.NVarChar);
   //sps.Value = str_Name;
   //sps2.Value = str_Pwd;
   //cmd.Parameters.Add(sps);
   //cmd.Parameters.Add(sps2);
#endregion