精进不休 .NET 4.0 (8) - ADO.NET Entity Framework 4.0 Self Tracking Entity
[索引页]
[源码下载]
作者： webabcd
介绍
ADO.NET Entity Framework 4.0 的新增功能
示例
1、Self Tracking Entity 的 Demo
SelfTrackingDemo/BLL.cs
[源码下载]
精进不休 .NET 4.0 (8) - ADO.NET Entity Framework 4.0 Self Tracking Entity
作者： webabcd
介绍
ADO.NET Entity Framework 4.0 的新增功能
- 对 Self Tracking Entity（实体状态自跟踪）的支持，基于 POCO
- WCF 结合 Self Tracking Entity 的应用
示例
1、Self Tracking Entity 的 Demo
SelfTrackingDemo/BLL.cs
/*
* ADO.NET Entity Framework 4.0 - 对 Self Tracking Entity（实体状态自跟踪）的支持，基于 POCO
* 1、不通过 WCF 使用 Self Tracking Entity 需要手动调用 StartTracking()
* 2、MarkAsAdded(), MarkAsModified(), MarkAsDeleted() 会自动 StartTracking()
* 3、ApplyChanges() 的作用是：绑定实体到上下文，通过 ChangeObjectState 改变实体的状态，通过 ChangeRelationshipState 改变关联实体的状态
*
* 本 Demo 演示如何通过 Self Tracking Entity 来实现对单表的增删改查
* 如果涉及到关联实体，可以参考 http://webabcd.blog.51cto.com/1787395/341378 中的“对外键的支持”的 Demo
*/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace SelfTrackingDemo
{
public class BLL
{
// 取全部产品类别的实体集合
List<ProductCategory> GetCategories() List<ProductCategory> GetCategories()
{
using (SelfTrackingEntities ctx = new SelfTrackingEntities())
{
var result = ctx.ProductCategories.ToList();
return result;
}
}
// 根据 id 取产品类别实体
ProductCategory GetCategory() ProductCategory GetCategory(int categoryId)
{
using (SelfTrackingEntities ctx = new SelfTrackingEntities())
{
var result = ctx.ProductCategories.Single(c => c.ProductCategoryID == categoryId);
return result;
}
}
// 根据产品类别实体更新数据库中的相关数据
void UpdateCategory() void UpdateCategory(ProductCategory category)
{
using (SelfTrackingEntities ctx = new SelfTrackingEntities())
{
// ApplyChanges() 的内部逻辑为：绑定实体到上下文，通过 ChangeObjectState 改变实体的状态，通过 ChangeRelationshipState 改变关联实体的状态
ctx.ProductCategories.ApplyChanges(category);
// 根据实体的状态，实现对实体的 添加、更新、删除 操作
var affectedRow = ctx.SaveChanges();
}
}
// 根据产品类别实体删除数据库中的相关数据
void DeleteCategory() void DeleteCategory(ProductCategory category)
{
// 标记该实体为删除状态
category.MarkAsDeleted();
UpdateCategory(category);
}
// 根据产品类别实体向数据库添加新的数据
void AddCategory() void AddCategory(ProductCategory category)
{
UpdateCategory(category);
}
}
}
* ADO.NET Entity Framework 4.0 - 对 Self Tracking Entity（实体状态自跟踪）的支持，基于 POCO
* 1、不通过 WCF 使用 Self Tracking Entity 需要手动调用 StartTracking()
* 2、MarkAsAdded(), MarkAsModified(), MarkAsDeleted() 会自动 StartTracking()
* 3、ApplyChanges() 的作用是：绑定实体到上下文，通过 ChangeObjectState 改变实体的状态，通过 ChangeRelationshipState 改变关联实体的状态
*
* 本 Demo 演示如何通过 Self Tracking Entity 来实现对单表的增删改查
* 如果涉及到关联实体，可以参考 http://webabcd.blog.51cto.com/1787395/341378 中的“对外键的支持”的 Demo
*/
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace SelfTrackingDemo
{
public class BLL
{
// 取全部产品类别的实体集合
List<ProductCategory> GetCategories() List<ProductCategory> GetCategories()
{
using (SelfTrackingEntities ctx = new SelfTrackingEntities())
{
var result = ctx.ProductCategories.ToList();
return result;
}
}
// 根据 id 取产品类别实体
ProductCategory GetCategory() ProductCategory GetCategory(int categoryId)
{
using (SelfTrackingEntities ctx = new SelfTrackingEntities())
{
var result = ctx.ProductCategories.Single(c => c.ProductCategoryID == categoryId);
return result;
}
}
// 根据产品类别实体更新数据库中的相关数据
void UpdateCategory() void UpdateCategory(ProductCategory category)
{
using (SelfTrackingEntities ctx = new SelfTrackingEntities())
{
// ApplyChanges() 的内部逻辑为：绑定实体到上下文，通过 ChangeObjectState 改变实体的状态，通过 ChangeRelationshipState 改变关联实体的状态
ctx.ProductCategories.ApplyChanges(category);
// 根据实体的状态，实现对实体的 添加、更新、删除 操作
var affectedRow = ctx.SaveChanges();
}
}
// 根据产品类别实体删除数据库中的相关数据
void DeleteCategory() void DeleteCategory(ProductCategory category)
{
// 标记该实体为删除状态
category.MarkAsDeleted();
UpdateCategory(category);
}
// 根据产品类别实体向数据库添加新的数据
void AddCategory() void AddCategory(ProductCategory category)
{
UpdateCategory(category);
}
}
}
SelfTrackingDemo/Demo.aspx
<%@ Page Language= "C#" AutoEventWireup= "true" CodeBehind= "Demo.aspx.cs" Inherits= "SelfTrackingDemo.Demo" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns= "http://www.w3.org/1999/xhtml">
<head runat= "server">
<title></title>
</head>
<body>
<form id= "form1" runat= "server">
<div>
<asp:ListView ID= "ListView1" runat= "server" DataSourceID= "ObjectDataSource1" DataKeyNames= "ProductCategoryID"
InsertItemPosition= "LastItem" OnItemUpdating= "ListView1_ItemUpdating">
<EditItemTemplate>
<tr style="">
<td>
<asp:Button ID= "UpdateButton" runat= "server" CommandName= "Update" Text= "Update" />
<asp:Button ID= "CancelButton" runat= "server" CommandName= "Cancel" Text= "Cancel" />
</td>
<td>
</td>
<td>
</td>
<td>
<asp:TextBox ID= "NameTextBox" runat= "server" Text= '<%# Bind("Name") %>' />
</td>
<td>
</td>
<td>
</td>
</tr>
</EditItemTemplate>
<InsertItemTemplate>
<tr style="">
<td>
<asp:Button ID= "InsertButton" runat= "server" CommandName= "Insert" Text= "Insert" />
<asp:Button ID= "CancelButton" runat= "server" CommandName= "Cancel" Text= "Clear" />
</td>
<td>
</td>
<td>
</td>
<td>
<asp:TextBox ID= "NameTextBox" runat= "server" Text= '<%# Bind("Name") %>' />
</td>
<td>
</td>
<td>
</td>
</tr>
</InsertItemTemplate>
<ItemTemplate>
<tr style="">
<td>
<asp:Button ID= "DeleteButton" runat= "server" CommandName= "Delete" Text= "Delete" />
<asp:Button ID= "EditButton" runat= "server" CommandName= "Edit" Text= "Edit" />
</td>
<td>
<asp:Label ID= "ProductCategoryIDLabel" runat= "server" Text= '<%# Eval("ProductCategoryID") %>' />
</td>
<td>
<asp:Label ID= "ParentProductCategoryIDLabel" runat= "server" Text= '<%# Eval("ParentProductCategoryID") %>' />
</td>
<td>
<asp:Label ID= "NameLabel" runat= "server" Text= '<%# Eval("Name") %>' />
</td>
<td>
<asp:Label ID= "rowguidLabel" runat= "server" Text= '<%# Eval("rowguid") %>' />
</td>
<td>
<asp:Label ID= "ModifiedDateLabel" runat= "server" Text= '<%# Eval("ModifiedDate") %>' />
</td>
</tr>
</ItemTemplate>
<LayoutTemplate>
<table id= "itemPlaceholderContainer" runat= "server" border= "0" style="">
<tr runat= "server" style="">
<th runat= "server">
</th>
<th runat= "server">
ProductCategoryID
</th>
<th runat= "server">
ParentProductCategoryID
</th>
<th runat= "server">
Name
</th>
<th runat= "server">
rowguid
</th>
<th runat= "server">
ModifiedDate
</th>
</tr>
<tr id= "itemPlaceholder" runat= "server">
</tr>
</table>
</LayoutTemplate>
</asp:ListView>
<asp:ObjectDataSource ID= "ObjectDataSource1" runat= "server" DataObjectTypeName= "SelfTrackingDemo.ProductCategory"
DeleteMethod= "DeleteCategory" InsertMethod= "AddCategory" SelectMethod= "GetCategories"
TypeName= "SelfTrackingDemo.BLL" OnInserting= "ObjectDataSource1_Inserting" OnDeleting= "ObjectDataSource1_Deleting">
</asp:ObjectDataSource>
</div>
</form>
</body>
</html>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns= "http://www.w3.org/1999/xhtml">
<head runat= "server">
<title></title>
</head>
<body>
<form id= "form1" runat= "server">
<div>
<asp:ListView ID= "ListView1" runat= "server" DataSourceID= "ObjectDataSource1" DataKeyNames= "ProductCategoryID"
InsertItemPosition= "LastItem" OnItemUpdating= "ListView1_ItemUpdating">
<EditItemTemplate>
<tr style="">
<td>
<asp:Button ID= "UpdateButton" runat= "server" CommandName= "Update" Text= "Update" />
<asp:Button ID= "CancelButton" runat= "server" CommandName= "Cancel" Text= "Cancel" />
</td>
<td>
</td>
<td>
</td>
<td>
<asp:TextBox ID= "NameTextBox" runat= "server" Text= '<%# Bind("Name") %>' />
</td>
<td>
</td>
<td>
</td>
</tr>
</EditItemTemplate>
<InsertItemTemplate>
<tr style="">
<td>
<asp:Button ID= "InsertButton" runat= "server" CommandName= "Insert" Text= "Insert" />
<asp:Button ID= "CancelButton" runat= "server" CommandName= "Cancel" Text= "Clear" />
</td>
<td>
</td>
<td>
</td>
<td>
<asp:TextBox ID= "NameTextBox" runat= "server" Text= '<%# Bind("Name") %>' />
</td>
<td>
</td>
<td>
</td>
</tr>
</InsertItemTemplate>
<ItemTemplate>
<tr style="">
<td>
<asp:Button ID= "DeleteButton" runat= "server" CommandName= "Delete" Text= "Delete" />
<asp:Button ID= "EditButton" runat= "server" CommandName= "Edit" Text= "Edit" />
</td>
<td>
<asp:Label ID= "ProductCategoryIDLabel" runat= "server" Text= '<%# Eval("ProductCategoryID") %>' />
</td>
<td>
<asp:Label ID= "ParentProductCategoryIDLabel" runat= "server" Text= '<%# Eval("ParentProductCategoryID") %>' />
</td>
<td>
<asp:Label ID= "NameLabel" runat= "server" Text= '<%# Eval("Name") %>' />
</td>
<td>
<asp:Label ID= "rowguidLabel" runat= "server" Text= '<%# Eval("rowguid") %>' />
</td>
<td>
<asp:Label ID= "ModifiedDateLabel" runat= "server" Text= '<%# Eval("ModifiedDate") %>' />
</td>
</tr>
</ItemTemplate>
<LayoutTemplate>
<table id= "itemPlaceholderContainer" runat= "server" border= "0" style="">
<tr runat= "server" style="">
<th runat= "server">
</th>
<th runat= "server">
ProductCategoryID
</th>
<th runat= "server">
ParentProductCategoryID
</th>
<th runat= "server">
Name
</th>
<th runat= "server">
rowguid
</th>
<th runat= "server">
ModifiedDate
</th>
</tr>
<tr id= "itemPlaceholder" runat= "server">
</tr>
</table>
</LayoutTemplate>
</asp:ListView>
<asp:ObjectDataSource ID= "ObjectDataSource1" runat= "server" DataObjectTypeName= "SelfTrackingDemo.ProductCategory"
DeleteMethod= "DeleteCategory" InsertMethod= "AddCategory" SelectMethod= "GetCategories"
TypeName= "SelfTrackingDemo.BLL" OnInserting= "ObjectDataSource1_Inserting" OnDeleting= "ObjectDataSource1_Deleting">
</asp:ObjectDataSource>
</div>
</form>
</body>
</html>
SelfTrackingDemo/Demo.aspx.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace SelfTrackingDemo
{
public partial class Demo : System.Web.UI.Page
{
void Page_Load() void Page_Load(object sender, EventArgs e)
{
}
void ObjectDataSource1_Inserting() void ObjectDataSource1_Inserting(object sender, ObjectDataSourceMethodEventArgs e)
{
var category = e.InputParameters[0] as ProductCategory;
category.rowguid = Guid.NewGuid();
category.ModifiedDate = DateTime.Now;
}
void ObjectDataSource1_Deleting() void ObjectDataSource1_Deleting(object sender, ObjectDataSourceMethodEventArgs e)
{
}
void ListView1_ItemUpdating() void ListView1_ItemUpdating(object sender, ListViewUpdateEventArgs e)
{
BLL bll = new BLL();
var category = bll.GetCategory((int)ListView1.DataKeys[e.ItemIndex].Value);
// 注意：这里一定要手动调用 StartTracking() 方法，用于跟踪实体状态的改变
category.StartTracking();
category.Name = e.NewValues[ "Name"].ToString();
bll.UpdateCategory(category);
ListView1.EditIndex = -1;
e.Cancel = true;
}
}
}
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
namespace SelfTrackingDemo
{
public partial class Demo : System.Web.UI.Page
{
void Page_Load() void Page_Load(object sender, EventArgs e)
{
}
void ObjectDataSource1_Inserting() void ObjectDataSource1_Inserting(object sender, ObjectDataSourceMethodEventArgs e)
{
var category = e.InputParameters[0] as ProductCategory;
category.rowguid = Guid.NewGuid();
category.ModifiedDate = DateTime.Now;
}
void ObjectDataSource1_Deleting() void ObjectDataSource1_Deleting(object sender, ObjectDataSourceMethodEventArgs e)
{
}
void ListView1_ItemUpdating() void ListView1_ItemUpdating(object sender, ListViewUpdateEventArgs e)
{
BLL bll = new BLL();
var category = bll.GetCategory((int)ListView1.DataKeys[e.ItemIndex].Value);
// 注意：这里一定要手动调用 StartTracking() 方法，用于跟踪实体状态的改变
category.StartTracking();
category.Name = e.NewValues[ "Name"].ToString();
bll.UpdateCategory(category);
ListView1.EditIndex = -1;
e.Cancel = true;
}
}
}
未完待续>>
OK
[源码下载]
[源码下载]