乐观并发代码

Question

我的学习课程有点问题。 我需要一个基本的乐观并发实现 我从Microsoft文档中的示例代码开始，然后编写一个测试用例来检查Optimistic条件。 代码是这样的：

private void TestConcorrenza_Click(object sender, EventArgs e)
{


   // Assumes connection is a valid SqlConnection.
    SqlDataAdapter adapter = new SqlDataAdapter("SELECT Id,Nome FROM DAti ORDER BY Id",FirstConnection);
    // The Update command checks for optimistic concurrency violations in the WHERE clause.
    adapter.UpdateCommand = new SqlCommand("UPDATE Dati Set Id = @Id, Nome = @Nome WHERE Id = @oldId AND Nome= @oldNome", FirstConnection);
    adapter.UpdateCommand.Parameters.Add( "@Id", SqlDbType.NChar, 5, "Id");
    adapter.UpdateCommand.Parameters.Add("@Nome", SqlDbType.NVarChar, 30, "Nome");
    // Pass the original values to the WHERE clause parameters.
    SqlParameter parameter = adapter.UpdateCommand.Parameters.Add("@oldId", SqlDbType.NChar, 5, "Id");
    parameter.SourceVersion = DataRowVersion.Original;
    parameter = adapter.UpdateCommand.Parameters.Add("@oldNome", SqlDbType.NVarChar, 30, "Nome");
    parameter.SourceVersion = DataRowVersion.Original;
    // Add the RowUpdated event handler.
    adapter.RowUpdated += new SqlRowUpdatedEventHandler(OnRowUpdated);
    DataSet dataSet = new DataSet();
    adapter.Fill(dataSet, "Dati");
    // Modify the DataSet contents.
    Update_for_Test();
    adapter.Update(dataSet, "Dati");
    foreach (DataRow dataRow in dataSet.Tables["Dati"].Rows)
    {
           if (dataRow.HasErrors)
           Console.WriteLine(dataRow [0] + "\n" + dataRow.RowError);
    }
    DataTable aTable = new DataTable();
    adapter.Fill(aTable);
    this.Test1.DataSource = aTable;
}



protected static void OnRowUpdated(object sender, SqlRowUpdatedEventArgs args)
{
    if (args.RecordsAffected == 0)
    {
        args.Row.RowError = "Optimistic Concurrency Violation Encountered";
        args.Status = UpdateStatus.SkipCurrentRow;
    }
}    

这是主要部分，这是测试用例：

public void Update_for_Test()
{
    SqlDataAdapter adapter = new SqlDataAdapter("SELECT Id,Nome FROM 
    Dati ORDER BY Id", SecondConnection);
    SqlDataAdapter ada= new SqlDataAdapter("UPDATE Dati SET  Nome 'Anna'                   WHERE Nome='Luca'", SecondConnection);
    DataSet dataSet = new DataSet();
    ada.Fill(dataSet, "Dati");
    adapter.Fill(dataSet, "Dati");
    DataTable aTable = new DataTable();
   adapter.Fill(aTable);
   this.Test2.DataSource = aTable;
}

我不明白为什么foreach中的情况是错误的。 有人有想法吗？ 好多了，干得好。