ExecuteNonQuery inside loop

Question

I'm trying to insert a database record inside a loop in C#.

It works when I hard code the values like this:

    string query3 = "INSERT INTO furniture (room_id,member_id) VALUES (222,333);";
    SqlCommand cmd3 = new SqlCommand(query3, sqlConnection3);
    sqlConnection3.Open();

    for (int i = 0; i < arrItemsPlanner.Length; i++)
    {
        try
            {
                cmd3.ExecuteNonQuery();
            }
            catch
            {
                return "Error: Item could not be saved";
            }
            finally
            {
                //Fail
            }
        }

But when I use parameterised queries it doesn't work - even if I hard code a value into the parameterised query like this:

    string query3 = "INSERT INTO furniture (room_id,member_id) VALUES (@room_id,333);";
    SqlCommand cmd3 = new SqlCommand(query3, sqlConnection3);
    sqlConnection3.Open();

    for (int i = 0; i < arrItemsPlanner.Length; i++)
    {
        try
            {
                cmd3.Parameters.Add("@room_id", System.Data.SqlDbType.Int);
                cmd3.Parameters["@room_id"].Value = 222;
                cmd3.ExecuteNonQuery();
            }
            catch
            {
                return "Error: Item could not be saved";
            }
            finally
            {
                //Fail
            }
        }

Can anyone see where I'm going wrong here?

Many thanks!

Answer 1

Tested & simple solution. If you are using parameters in loop You need to clear the parameters after execution of query. So you can use that

cmd3.executeNonQuery();
cmd3.Parameters.Clear();

Answer 2

It looks like you are adding to the command's parameter collection over and over. Clear it with each iteration.

I would also suggest throwing the actual exception so you can see what the problem is.