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[EF]使用EF简单增删改查

目录

认识EF

添加数据

删除数据

修改数据

查询数据

总结

认识EF

ADO.NET Entity Framework 是微软以ADO.NET为基础所发展出来的对象关系对伊(O/R Mapping)解决方案,早起被称为ObjectSpage,最新版本EF6。

实体框架Entity Framework是ADO.NET中的一组支持面向数据的软件应用程序的技术。是微软的一个ORM框架。

什么是O/R Mapping

广义上,ORM指的是面向对象模型和关系数据库的数据结构之间的相互转换。

狭义上,ORM可以被认为是,基于关系数据库的数据存储,实现一个虚拟的面向对象的数据访问接口。理想情况下,基于这样一个面向对象的接口,持久化一个OO对象应该不需要了解任何关系型数据存储数据的实现细节。

添加数据

测试用数据库

 1 USE [Wolfy.Shop] 2 GO 3  4 /****** Object:  Table [dbo].[TB_Customer]    Script Date: 2014/7/29 20:01:56 ******/ 5 SET ANSI_NULLS ON 6 GO 7  8 SET QUOTED_IDENTIFIER ON 9 GO10 11 CREATE TABLE [dbo].[TB_Customer](12     [ID] [uniqueidentifier] NOT NULL,13     [Name] [nvarchar](32) NULL,14     [Address] [nvarchar](100) NULL,15     [Gender] [bit] NULL,16  CONSTRAINT [PK_CustomerID] PRIMARY KEY CLUSTERED 17 (18     [ID] ASC19 )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]20 ) ON [PRIMARY]21 22 GO
TB_Customer
 1 USE [Wolfy.Shop] 2 GO 3  4 /****** Object:  Table [dbo].[TB_Order]    Script Date: 2014/7/29 20:02:47 ******/ 5 SET ANSI_NULLS ON 6 GO 7  8 SET QUOTED_IDENTIFIER ON 9 GO10 11 CREATE TABLE [dbo].[TB_Order](12     [ID] [int] NOT NULL,13     [OrderName] [nvarchar](1000) NULL,14     [CreateDate] [datetime] NULL,15     [customerId] [uniqueidentifier] NULL,16  CONSTRAINT [PK_TB_Order] PRIMARY KEY CLUSTERED 17 (18     [ID] ASC19 )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]20 ) ON [PRIMARY]21 22 GO23 24 ALTER TABLE [dbo].[TB_Order]  WITH CHECK ADD  CONSTRAINT [FK_Customer_Order] FOREIGN KEY([customerId])25 REFERENCES [dbo].[TB_Customer] ([ID])26 GO27 28 ALTER TABLE [dbo].[TB_Order] CHECK CONSTRAINT [FK_Customer_Order]29 GO
TB_Order

工具VS2013,SQL SERVER2012
在使用EF的时候发现,跟之前的版本差别还是挺大的,有些方法的名字都改了。这里记录一下,使用的时候方便查找吧。

测试页面

 1 <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="AddCustomer.aspx.cs" Inherits="Wofly.EFDemo.AddCustomer" %> 2  3 <!DOCTYPE html> 4  5 <html xmlns="http://www.w3.org/1999/xhtml"> 6 <head runat="server"> 7     <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> 8     <title></title> 9 </head>10 <body>11     <form id="form1" runat="server">12         <div>13             <asp:Button Text="添加" CommandArgument="add" runat="server" ID="btnAdd" OnClick="btnAdd_Click" />14             <table>15                 <tr>16                     <td>用户名:</td>17                     <td>18                         <asp:TextBox runat="server" ID="txtUserName" ClientIDMode="Static" /></td>19                 </tr>20                 <tr>21                     <td>用户地址:</td>22                     <td>23                         <asp:TextBox runat="server" ID="txtAddress" ClientIDMode="Static" /></td>24                 </tr>25                 <tr>26                     <td>性别:</td>27                     <td>28                         <asp:RadioButton runat="server" Checked="true" ID="rdbMan" Text="男" GroupName="gender" />29                         <asp:RadioButton GroupName="gender" runat="server" ID="rdbFemale" Text="女" />30                     </td>31                 </tr>32             </table>33             <asp:Repeater runat="server" ID="rptCustomerList">34                 <HeaderTemplate>35                     <table>36                         <tr>37                             <th>序号</th>38                             <th>用户名</th>39                             <th>地址</th>40                             <th>性别</th>41                             <th>操作</th>42                         </tr>43                 </HeaderTemplate>44                 <ItemTemplate>45                     <tr>46                         <td><%#Container.ItemIndex+1 %></td>47                         <td><%#Eval("Name") %></td>48                         <td><%#Eval("Address") %></td>49                         <td><%#Convert.ToBoolean(Eval("Gender"))==true?"":"" %></td>50                         <td>51                             <asp:LinkButton Text="编辑" runat="server" OnClick="lnkEdit_Click" CommandName="Edit" CommandArgument=‘<%#Eval("ID") %>‘ ID="lnkEdit" /><asp:LinkButton Text="删除" runat="server" OnClick="lnkEdit_Click" ID="lnkDelete" CommandName="Delete" CommandArgument=‘<%#Eval("ID") %>‘ /></td>52                     </tr>53                 </ItemTemplate>54                 <FooterTemplate>55                     </table>56                 </FooterTemplate>57             </asp:Repeater>58         </div>59     </form>60 </body>61 </html>
AddCustomer.aspx

增加用户

1                ShopEntities shopEntities = new ShopEntities();2                 TB_Customer tb_CustomerAdd = new TB_Customer() { ID = Guid.NewGuid(), Name = txtUserName.Text, Address = txtAddress.Text, Gender = rdbMan.Checked ? true : false };3                 shopEntities.TB_Customer.Add(tb_CustomerAdd);4                 int intResult = shopEntities.SaveChanges();5                 if (intResult > 0)6                 {7                     DataInit();8                 }

 

删除数据

1                    shopEntities.TB_Customer.Remove(tb_Customer);2                     if (shopEntities.SaveChanges() > 0)3                     {4                         this.DataInit();5                     }

 

修改数据

 1                 ShopEntities shopEntities = new ShopEntities(); 2                 var customer = from c in shopEntities.TB_Customer 3                                where c.ID == new Guid(btn.CommandArgument) 4                                select c; 5                 TB_Customer tb_CustomerUpdate = customer.FirstOrDefault<TB_Customer>(); 6                 //将 对象 添加到 EF中    7                 tb_CustomerUpdate.Name = txtUserName.Text; 8                 tb_CustomerUpdate.Address = txtAddress.Text; 9                 tb_CustomerUpdate.Gender = rdbMan.Checked ? true : false;10                 //是否修改11                 shopEntities.Entry<TB_Customer>(tb_CustomerUpdate).State = System.Data.EntityState.Modified;12                 //一次性 生成sql语句到数据库执行            13                 shopEntities.SaveChanges();

 

查询数据

1         private void DataInit()2         {3             ShopEntities shopEntities = new ShopEntities();4             var customers = from c in shopEntities.TB_Customer5                             select c;6             this.rptCustomerList.DataSource = customers.ToList();7             this.rptCustomerList.DataBind();8         }

 

总结

新技术更新可真快,这里只是记录增删改查的方法,也没具体描述,只是影响中感觉跟ef4差别很大。这里记录一下,使用起来的时候,希望能快速上手。