EF之Database First

Entity Framework支持Database First、Model First和Code Only三种开发模式，各模式的开发流程大相径庭，开发体验完全不一样。我综合考虑。主要适用Database First和Code only，所以总结着两种模式！

一、Database First

工具sql 2008和VS2010

建了一个Text数据表，表内容如下

图一：数据库及表结构

建一个解决方案，同时新建一个EFTest的web项目，然后添加一个DatabaseFirst的类库

图二：解决方案及项目结构

在Visual Studio解决方案的DatabaseFirst项目中，添加一个名为DatabaseFirst.edmx的ADO.NET实体数据模型，如下图所示：

图三：添加ADO.NET实体数据模型

点击“添加”按钮后，进入创建实体数据模型向导的选择模型内容界面，如下图所示：

图四：选择从数据库生成模型

选择“从数据库生成”图标，并点击“下一步”按钮，进入选择数据连接界面，如下图所示：

图五：设置数据连接

指定你的本地数据连接，选择“是，在连接字符串中包括敏感数据”选项，并为实体连接设置名称为“DatabaseFirst”，点击“下一步”按钮，进入选择数据库对象界面，如下图所示：

图六选择数据库对象

可供选择的数据库对象包括表、视图和存储过程。按上图所示设置后，点击“完成”按钮，Visual Studio将自动完成从Database到实体数据模型的生成工作。如下图所示：

图七由数据库生成的实体对象模型

如图生成实体对象模型的时候会生成一个App.config，会有这样一段代码，就是数据库连接的代码，我们可以把他考到web.config中，代码如下图：

<connectionStrings>
        <add name="TestEntities" 
             connectionString="metadata=res://*/DatabaseFirst.csdl|res://*/DatabaseFirst.ssdl|res://*/DatabaseFirst.msl;
             provider=System.Data.SqlClient;
             provider connection string=&quot;
             data source=ASIAIT-SERVER\SERVER2008R2;
             initial catalog=Test;
             persist security info=True;
             user id=sa;
             password=123;
             multipleactiveresultsets=True;
             App=EntityFramework&quot;" 
             providerName="System.Data.EntityClient" />
    </connectionStrings>

然后在web项目中添加List.aspx进行业务的增删改查：

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="List.aspx.cs" Inherits="EFTest.List" %>

<!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>
    <style type="text/css">
        .style1
        {
            width: 42px;
        }
        .style2
        {
            width: 166px;
        }
        .style3
        {
            width: 57px;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
        <asp:Label ID="lblError" runat="server" ForeColor="Red" />
    <div id="toolbar">
        帐号：
        <asp:TextBox ID="tbAccount" runat="server" />
        <asp:Button ID="btnSearch" runat="server" Text="搜索" />
    </div>
<asp:ListView ID="lvUsers" runat="server" onitemdeleting="lvUsers_ItemDeleting" 
            onitemediting="lvUsers_ItemEditing"  DataKeyNames = "ID" 
            onitemupdating="lvUsers_ItemUpdating">
    <LayoutTemplate>
        <table border="1" width="800">
            <thead>
                <tr>
                    <th>ID</th>
                    <th width="200">姓名</th>
                    <th width="60">性别</th>
                    <th width="60">年龄</th>
                    <th width="60">电话</th>
                    <th width="150">操作</th>
                </tr>
            </thead>
            <tbody>
                <tr id="itemPlaceholder" runat="server"></tr>
            </tbody>
        </table>
    </LayoutTemplate>
    <ItemTemplate>
        <tr>
            <td><a href='Form.aspx?ID=<%# Eval("ID") %>' target="_blank"><%# Eval("ID") %></a></td>
            <td><%# Eval("Name") %></td>
            <td><%# Eval("Sex") %></td>
            <td><%# Eval("Age") %></td>
            <td><%# Eval("Phone")%></td>
            <td>
                <asp:Button ID="btnEdit" runat="server" Text="修改" CommandName="Edit" CommandArgument='<%#Eval("ID")%>'/>
                <asp:Button ID="ibtnDelete" runat="server" Text="删除" CommandName="Delete" CommandArgument='<%#Eval("ID")%>' OnClientClick="return confirm('删除的数据不可恢复，确定要执行删除操作吗？');" />
            </td>
        </tr>
    </ItemTemplate>
<EditItemTemplate>
    <tr>
        <td><asp:TextBox ID="tbId" runat="server" Text='<%# Bind("ID") %>' /></td>
        <td><asp:TextBox ID="txtName" runat="server"  Text='<%# Eval("Name") %>'/></td>
        <td><asp:DropDownList ID="dropSex" runat="server" Height="30px" Width="145px">
                    <asp:ListItem>男</asp:ListItem>
                    <asp:ListItem>女</asp:ListItem>
                </asp:DropDownList></td>
        <td><asp:TextBox ID="txtAge" runat="server" Text='<%# Eval("Age") %>'/></td>
        <td><asp:TextBox ID="txtphone" runat="server" Text='<%# Eval("Phone")%>' /></td>
        <td>
            <asp:Button ID="tbnEdit" runat="server" Text="保存" CommandName="Update" ValidationGroup="Update" />
            <asp:Button ID="tbnCancel" runat="server" Text="取消" CommandName="Cancel" CausesValidation="false" />
        </td>
    </tr>
</EditItemTemplate>
    <EmptyDataTemplate>
        没有符合条件的数据
    </EmptyDataTemplate>
</asp:ListView>
<table border="1" width="800">
<tr>
            <td class="style1">姓名</td>
            <td class="style2"><asp:TextBox ID="tbName" runat="server"  /></td>
            <td class="style3">性别</td>
            <td>
                <asp:DropDownList ID="dropSex" runat="server" Height="30px" Width="145px">
                    <asp:ListItem>男</asp:ListItem>
                    <asp:ListItem>女</asp:ListItem>
                </asp:DropDownList>
            </td>
            <td></td>
        </tr>
        <tr>
            <td class="style1">年龄</td>
            <td class="style2"><asp:TextBox ID="tbAge" runat="server" /></td>
            <td class="style3">电话</td>
            <td><asp:TextBox ID="tbPhone" runat="server" /></td>
            <td><asp:Button ID="btnAdd" runat="server" Text="添加" CommandName="Insert" 
                    ValidationGroup="Insert" onclick="btnAdd_Click" /></td>
        </tr>
        </table>
    </form>
</body>
</html>

后代代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using DatabaseFirst;
using System.Xml.Linq;

namespace EFTest
{
    public partial class List : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                this.lblError.Text = string.Empty;
                BindDate();
           }
        }
        /// <summary>
        /// 绑定数据
        /// </summary>
        public void BindDate()
        {
            var db = new DatabaseFirst.TestEntities();
            var list = db.Users.Where(o => "" == "");

            this.lvUsers.DataSource = list;
            this.lvUsers.DataBind();
        }

        /// <summary>
        /// 添加用户
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void btnAdd_Click(object sender, EventArgs e)
        {

            using (var db = new DatabaseFirst.TestEntities())
            {
                if (db.Users.Count(o => o.Name == tbName.Text) > 0)
                {
                    this.lblError.Text = "姓名已被占用！";
                    return;
                }

                var user = new User();
                user.Name = tbName.Text;
                user.Phone = tbPhone.Text;
                user.Sex = dropSex.SelectedValue;
                user.Age = Convert.ToInt32(tbAge.Text);
                user.RoleId = 1;
                db.Users.AddObject(user);

db.SaveChanges();
}

BindDate();
}

        /// <summary>
        /// 编辑用户
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void lvUsers_ItemEditing(object sender, ListViewEditEventArgs e)
        {
            lvUsers.EditIndex = e.NewEditIndex;
            BindDate();
        }

        /// <summary>
        /// 更新数据
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void lvUsers_ItemUpdating(object sender, ListViewUpdateEventArgs e)
        {
            int id = Convert.ToInt32(lvUsers.DataKeys[e.ItemIndex].Value.ToString());
            string name = ((TextBox)(lvUsers.Items[e.ItemIndex].FindControl("txtName"))).Text;
            string age = ((TextBox)(lvUsers.Items[e.ItemIndex].FindControl("txtAge"))).Text;
            string phone = ((TextBox)(lvUsers.Items[e.ItemIndex].FindControl("txtPhone"))).Text;
            string sex = ((DropDownList)(lvUsers.Items[e.ItemIndex].FindControl("dropSex"))).SelectedValue;
            using (var db = new DatabaseFirst.TestEntities())
            {
                var user = db.Users.SingleOrDefault(o => o.ID == id);

                if (db.Users.Count(o => o.Name == name && o.ID != user.ID) > 0)
                {
                    this.lblError.Text = "姓名已被占用！";
                    e.Cancel = true;
                }

                user.ID = id;
                user.Name = name;
                user.Phone = phone;
                user.Sex = sex;
                user.Age = Convert.ToInt32(age);
                user.RoleId = 1;
                db.Users.ApplyCurrentValues(user);

                db.SaveChanges();
                BindDate();
            }
        }

        /// <summary>
        /// 删除数据
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        protected void lvUsers_ItemDeleting(object sender, ListViewDeleteEventArgs e)
        {
            int id = Convert.ToInt32(lvUsers.DataKeys[e.ItemIndex].Value.ToString());
            using (var db = new DatabaseFirst.TestEntities())
            {
                var user = db.Users.SingleOrDefault(o => o.ID == id);
                db.Users.DeleteObject(user);
                db.SaveChanges();
                BindDate();
            }
        }

}
}

最后运行效果：

posted on 2013-03-20 09:48 过往云烟阅读(478) 评论(0) 编辑收藏举报