ADO.NET事物处理

public void SetValue()
    {
        SqlConnection connection = new SqlConnection("ConnectionString");
        connection.Open();
        SqlTransaction tran = new SqlTransaction();
        SqlCommand command = new SqlCommand();
        command.Connection = connection;
        command.Transaction = tran;
        try
        {
            command.CommandText = "insert ";
            command.ExecuteNonQuery();
            command.CommandText = "upadte ";
            command.ExecuteNonQuery();
            tran.Commit();
        }
        catch (Exception ex)
        {
            tran.Rollback();
        }
        finally
        {
            connection.Close();
        }
    }