在实体数据模型 (EDM) 中，AdventureWorks 数据绑定应用程序包含两个用于加载和修改数据的事件处理程序。当用户单击 buttonGetHeader 时，将运行加载 SalesOrderHeader 及其关联 SalesOrderDetail 实体的代码。对 SalesOrderDetail 实体所包含数据的修改在订单详细信息网格事件处理程序 cellEndEdit 中提交。
应用程序代码
AdventureWorks 数据绑定应用程序中使用的 Windows 主窗体的代码如下所示：
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using AdventureWorksModel;
using System.Data.Objects;
namespace AdWksSalesWinDataBind
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
objCtx = new AdventureWorksEntities();
}
private void buttonGetHeader_Click(object sender, EventArgs e)
{
if (textBoxOrderId.Text.Equals(""))
{
MessageBox.Show("Add Sales Order Header Number",
"No Header Number");
return;
}
ObjectParameter parameter =
new ObjectParameter("p", Int32.Parse(textBoxOrderId.Text));
dataGridViewSOHeader.DataSource = objCtx.SalesOrderHeader.Where(
"it.SalesOrderID == @p", parameter).Execute(MergeOption.OverwriteChanges);
if(objCtx.SalesOrderHeader.Where(
"it.SalesOrderID == @p", parameter).Any())
{
SalesOrderHeader resultHeader =
objCtx.SalesOrderHeader.Where(
"it.SalesOrderID == @p", parameter).First();
resultHeader.SalesOrderDetail.Load();
dataGridViewOrderDetails.DataSource = resultHeader.SalesOrderDetail;
}
else
MessageBox.Show(
"No Sales Order Header matches this key",
"No Match");
}
private void Form1_FormClosing(object sender,
FormClosingEventArgs e)
{
objCtx.Connection.Close();
objCtx.Dispose();
}
private void dataGridViewSOHeader_CellEndEdit(object sender,
DataGridViewCellEventArgs e)
{
objCtx.SaveChanges();
}
private void dataGridViewOrderDetails_CellEndEdit(object sender,
DataGridViewCellEventArgs e)
{
objCtx.SaveChanges();
ObjectParameter parameter =
new ObjectParameter("p", Int32.Parse(textBoxOrderId.Text));
SalesOrderHeader header =
objCtx.SalesOrderHeader.Where(
"it.SalesOrderID == @p", parameter).FirstOrDefault();
// Refresh the SalesOrderHeader in the grid.
objCtx.Refresh(RefreshMode.StoreWins, header);
}
private void buttonAddSalesOrder_Click(object sender, EventArgs e)
{
FormAddSalesOrderDetail formAddSODetail = new FormAddSalesOrderDetail(objCtx);
DialogResult dlgResult = formAddSODetail.ShowDialog(this);
if(dlgResult.Equals(DialogResult.OK))
{
ObjectParameter parameter =
new ObjectParameter("p", Int32.Parse(textBoxOrderId.Text));
SalesOrderHeader header =
objCtx.SalesOrderHeader.Where(
"it.SalesOrderID == @p", parameter).FirstOrDefault();
// Refresh the SalesOrderDetails in the grid.
buttonGetHeader_Click(null, null);
}
}
private void textBoxOrderId_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
if (e.KeyCode.Equals(Keys.Return))
buttonGetHeader_Click(this, System.EventArgs.Empty);
}
}
}
另请参见
概念
Adventure Works 数据绑定（EDM 示例应用程序）
AdventureWorks 数据绑定示例添加 SalesOrderDetail 窗体（EDM 示例应用程序）