将datagrid绑定到datareader [英] Bind datagrid to datareader

问题描述

我希望能够在文本框中输入SQL并在WPF Datagrid中显示结果。我想从 SqlDataReader 开始，然后将datagrid的 ItemsSource 设置为数据读取器：

I want to be able to enter SQL into a textbox and display the results in a WPF Datagrid. I thought to start with an SqlDataReader, and set the datagrid's ItemsSource to the data reader:

using (var cmd = conn.CreateCommand()) {
    cmd.CommandText = sql.Text;
    sqlResults.ItemsSource = cmd.ExecuteReader();
}

但这失败，并出现以下错误：无效尝试在读者关闭时调用FieldCount ，据我理解，这意味着WPF开始阅读行对象的 FieldCount 属性时， using 块已经退出。

but this fails with the following error: Invalid attempt to call FieldCount when reader is closed, which I understand to mean that by the time WPF gets around to reading the FieldCount property of the row object, the using block has already been exited.

所以我尝试使用LINQ和 ToList ，以获得保留在内存中的内容：

So I tried using LINQ and ToList, to get something that would persist in memory:

sqlResults.ItemsSource = cmd.ExecuteReader().Cast<DbDataRecord>().ToList();

但这仅显示每一行的 FieldCount，这显然是唯一 DbDataRecord 有。

but this only displays the 'FieldCount' for each row, which is apparently the only property which DbDataRecord has.

我考虑过的一些解决方案：

Some solutions I have considered:

• 绑定到DataTable而不是DataReader？但是我不需要编辑功能。


• 是否将每一行选择到内存数据结构中？我可以使用什么数据结构？我不能使用匿名类型，因为列的名称和类型根据SQL语句而变化。如果我使用 List< object> ，数据网格将如何知道为列表中的每个对象生成列？


• 创建自定义类型描述符？

• Bind to a DataTable instead of a DataReader? But I don't need editing capabilities.
• Select each row into an in-memory data structure? What data structure could I use? I can't use anonymous types, because the names and types of the columns change based on the SQL statement. If I use List<object>, how will the datagrid know to generate columns for each object in the list?
• Create a custom type descriptor? It seems like overkill.

但是我觉得解决方案应该非常简单容易。我在这里错过了一些基本的东西吗？

But I feel the solution should be very simple and easy. Am I missing something basic here?

推荐答案

也许DataTable是过分的，但是它可以满足您的需要。

Maybe a DataTable is overkill but it does what you need it to do.

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