每次添加新行时都应该调用 AcceptChanges() 吗?

Should AcceptChanges() be called every time a new row is added?(每次添加新行时都应该调用 AcceptChanges() 吗?)

问题描述

推荐

while (reader.Read())  
{
    table.Rows.Add(
            new object[] { reader[0], reader[1], reader[2], reader[3] }
    );  
    table.AcceptChanges();
}  

或

while (reader.Read())  
{
    table.Rows.Add(
            new object[] { reader[0], reader[1], reader[2], reader[3] }
    );  
}  
table.AcceptChanges();

注意 table.AcceptChanges 的放置位置.

Note where the table.AcceptChanges is placed.

编辑 1

这里是代码块:

protected void Page_Load(object sender, EventArgs e)
{
    IDataReader reader = cust.GetCustomerOrderSummary("99999");
    using (DataSet ds = new DataSet())
    {
        using (DataTable table =
                new DataTable { TableName = "OrderSummary" })
        {
            DataColumn idColumn = table.Columns.Add("number", typeof(int));
            table.Columns.Add("name", typeof(string));
            table.Columns.Add("quantity", typeof(int));
            table.Columns.Add("prev_quantity", typeof(int));
            table.PrimaryKey = new DataColumn[] { idColumn };
            while (reader.Read())
            {
                table.Rows.Add(
                  new object[]{ reader[0], reader[1], reader[2], reader[3] }
                );
                table.AcceptChanges();
            }
            ds.Tables.Add(table);
            rptCustomerOrder report =
                    new rptCustomerOrder { DataSource = ds };
            ReportViewer1.Report = report;
        }
    }
}

<小时>

编辑 2
在阅读了 MSDN 文章 here 我决定根据以下语句(来自文章)将 AcceptChanges() 置于循环之外:

EDIT 2
After reading the MSDN article here I decided to place the AcceptChanges() outside the loop based on the following statement (from the article):

在 DataTable 级别调用 AcceptChanges 会导致调用每个 DataRow 的 AcceptChanges 方法.

Calling AcceptChanges at the DataTable level causes the AcceptChanges method for each DataRow to be called.

推荐答案

添加新行后调用AcceptChanges实际上会变成你新添加的DataRow的DataRowState 从 Added 到 Unchanged.如果您继续使用它，您可能失去对新添加行的跟踪，并且在持久化时.ADO.NET 无法识别需要插入数据库的行.所以明智地选择这个选项，你甚至可能不需要它.