Windows Phone 7 本地数据库SQL Server CE（芒果更新）
在Windows Phone的第一个版本7.0版本里面是没有本地数据库支持的，要使用数据库只能够使用第三方的数据库组件。Windows Phone的本地数据库SQL Server CE是7.1版本即芒果更新的新特性，所以你要在应用程序中使用SQL Server CE数据库必须使用Windows Phone 7.1的API才行。
下面用一个实例演示如何使用SQL Server CE数据库。
（1）创建数据表以及数据库的数据上下文DateContent
先创建一个员工信息表，用于保存员工的名字和简介，员工表有一个自增的ID。
EmployeeTable.cs
using System.Data.Linq.Mapping;
using System.ComponentModel;
namespace SQLServerDemo
{
[Table]
public class EmployeeTable : INotifyPropertyChanged, INotifyPropertyChanging
{
// 定义员工表独立增长ID，设置为主键
private int _employeeId;
[Column(IsPrimaryKey = true, IsDbGenerated = true, DbType = "INT NOT NULL Identity", CanBeNull = false, AutoSync = AutoSync.OnInsert)]
public int EmployeeID
{
get
{
return _employeeId;
}
set
{
if (_employeeId != value)
{
NotifyPropertyChanging("EmployeeID");
_employeeId = value;
NotifyPropertyChanged("EmployeeID");
}
}
}
// 定义员工名字字段
private string _employeeName;
[Column]
public string EmployeeName
{
get
{
return _employeeName;
}
set
{
if (_employeeName != value)
{
NotifyPropertyChanging("EmployeeName");
_employeeName = value;
NotifyPropertyChanged("EmployeeName");
}
}
}
//定义员工简介字段
private string _employeeDesc;
[Column]
public string EmployeeDesc
{
get
{
return _employeeDesc;
}
set
{
if (_employeeDesc != value)
{
NotifyPropertyChanging("EmployeeDesc");
_employeeDesc = value;
NotifyPropertyChanged("EmployeeDesc");
}
}
}
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
//用来通知页面表的字段数据产生了改变
private void NotifyPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
#region INotifyPropertyChanging Members
public event PropertyChangingEventHandler PropertyChanging;
// 用来通知数据上下文表的字段数据将要产生改变
private void NotifyPropertyChanging(string propertyName)
{
if (PropertyChanging != null)
{
PropertyChanging(this, new PropertyChangingEventArgs(propertyName));
}
}
#endregion
}
}创建数据库的DataContent，定义一个EmployeeDataContext类来继承DataContext，在EmployeeDataContext中定义数据库连接字符串，以及员工信息表。
EmployeeDataContext.cs
using System.Data.Linq;
namespace SQLServerDemo
{
public class EmployeeDataContext : DataContext
{
// 数据库链接字符串
public static string DBConnectionString = "Data Source=isostore:/Employee.sdf";
// 传递数据库连接字符串到DataContext基类
public EmployeeDataContext(string connectionString)
: base(connectionString)
{ }
// 定义一个员工信息表
public Table<EmployeeTable> Employees;
}
}（2） 创建页面数据绑定的集合
EmployeeCollection.cs
using System.ComponentModel;
using System.Collections.ObjectModel;
namespace SQLServerDemo
{
//EmployeeCollection用于跟页面的数据绑定
public class EmployeeCollection : INotifyPropertyChanged
{
//定义ObservableCollection来绑定页面的数据
private ObservableCollection<EmployeeTable> _employeeTables;
public ObservableCollection<EmployeeTable> EmployeeTables
{
get
{
return _employeeTables;
}
set
{
if (_employeeTables != value)
{
_employeeTables = value;
NotifyPropertyChanged("EmployeeTables");
}
}
}
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
//用于通知属性的改变
private void NotifyPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
}
}（3）创建数据库，绑定数据，实现员工信息表的增删改查操作。
在App.xaml.cs中的程序加载事件中进行创建数据库
private void Application_Launching(object sender, LaunchingEventArgs e)
{
//如果数据库不存在则创建一个数据库
using (EmployeeDataContext db = new EmployeeDataContext(EmployeeDataContext.DBConnectionString))
{
if (db.DatabaseExists() == false)
{
//创建一个数据库
db.CreateDatabase();
}
}
}MainPage.xaml文件代码
<phone:PhoneApplicationPage
x:Class="SQLServerDemo.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:phone="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone"
xmlns:shell="clr-namespace:Microsoft.Phone.Shell;assembly=Microsoft.Phone"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="768"
FontFamily="{StaticResource PhoneFontFamilyNormal}"
FontSize="{StaticResource PhoneFontSizeNormal}"
Foreground="{StaticResource PhoneForegroundBrush}"
SupportedOrientations="Portrait" Orientation="Portrait"
shell:SystemTray.IsVisible="True">
<Grid x:Name="LayoutRoot" Background="Transparent">
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,17,0,28">
<TextBlock x:Name="ApplicationTitle" Text="MY APPLICATION" Style="{StaticResource PhoneTextNormalStyle}"/>
<TextBlock x:Name="PageTitle" Text="SQL Server" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}"/>
</StackPanel>
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<Grid Margin="0,0,0,385">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="Auto" />
</Grid.ColumnDefinitions>
<TextBlock FontSize="30" Height="37" HorizontalAlignment="Left" Margin="12,18,0,0" Name="textBlock1" Text="员工名字:" VerticalAlignment="Top" />
<TextBox Name="name" Text="" Margin="145,0,6,144" />
<TextBlock FontSize="30" Height="52" HorizontalAlignment="Left" Margin="18,74,0,0" Name="textBlock2" Text="简介：" VerticalAlignment="Top" />
<TextBox Height="79" HorizontalAlignment="Left" Margin="93,65,0,0" Name="desc" Text="" VerticalAlignment="Top" Width="357" />
<Button
Content="保存" x:Name="addButton"
Click="addButton_Click" Margin="219,132,6,6" />
</Grid>
<ListBox x:Name="toDoItemsListBox" ItemsSource="{Binding EmployeeTables}" Margin="12,241,12,0" Width="440">
<ListBox.ItemTemplate>
<DataTemplate>
<Grid HorizontalAlignment="Stretch" Width="440">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="50" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="100" />
</Grid.ColumnDefinitions>
<TextBlock
Text="{Binding EmployeeName}"
FontSize="{StaticResource PhoneFontSizeLarge}"
Grid.Column="1"
VerticalAlignment="Center"/>
<Button
Grid.Column="2"
x:Name="deleteButton"
BorderThickness="0"
Margin="0"
Click="deleteButton_Click"
Content="删除">
</Button>
<Button
Grid.Column="1"
x:Name="editButton"
BorderThickness="0"
Margin="209,0,81,0"
Click="editButton_Click"
Content="编辑" Grid.ColumnSpan="2">
</Button>
</Grid>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</Grid>
</Grid>
</phone:PhoneApplicationPage>MainPage.xaml.cs文件代码
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using Microsoft.Phone.Controls;
using System.Collections.ObjectModel;
namespace SQLServerDemo
{
public partial class MainPage : PhoneApplicationPage
{
// 创建DataContext实例用于用于操作本地的数据库
private EmployeeDataContext employeeDB;
private EmployeeCollection employeeCol = new EmployeeCollection();
public MainPage()
{
InitializeComponent();
//连接数据库并初始化DataContext实例
employeeDB = new EmployeeDataContext(EmployeeDataContext.DBConnectionString);
// 使用Linq查询语句查询EmployeeTable表的所有数据
var employeesInDB = from EmployeeTable employee in employeeDB.Employees
select employee;
// 将查询的结果返回到页面数据绑定的集合里面
employeeCol.EmployeeTables = new ObservableCollection<EmployeeTable>(employeesInDB);
//赋值给当前页面的DataContext用于数据绑定
this.DataContext = employeeCol;
}
/// <summary>
/// 删除操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void deleteButton_Click(object sender, RoutedEventArgs e)
{
// 获取单击的按钮实例
var button = sender as Button;
if (button != null)
{
//获取当前按钮绑定的DataContext，即当前的删除的EmployeeTable实例
EmployeeTable employeeForDelete = button.DataContext as EmployeeTable;
//移除绑定集合里面要删除的EmployeeTable记录
employeeCol.EmployeeTables.Remove(employeeForDelete);
// 移除数据库里面要删除的EmployeeTable记录
employeeDB.Employees.DeleteOnSubmit(employeeForDelete);
//保存数据库的改变
employeeDB.SubmitChanges();
}
}
/// <summary>
/// 保存操作，处理新增和编辑员工信息
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void addButton_Click(object sender, RoutedEventArgs e)
{
//控制员工名字和简介不能为空
if (name.Text != "" && desc.Text != "")
{
if (State.Count>0 && State["employee"] != null )//编辑状态
{
//获取编辑的EmployeeTable对象
EmployeeTable employee = (EmployeeTable)State["employee"];
employee.EmployeeName = name.Text;
employee.EmployeeDesc = desc.Text;
//保存数据库的改变
employeeDB.SubmitChanges();
//添加绑定集合的数据,因为在单击编辑的时候移除了
employeeCol.EmployeeTables.Add(employee);
State["employee"] = null;
}
else//新增状态
{
//创建一条表的数据
EmployeeTable newEmployee = new EmployeeTable { EmployeeName = name.Text, EmployeeDesc = desc.Text };
//添加绑定集合的数据
employeeCol.EmployeeTables.Add(newEmployee);
//插入数据库
employeeDB.Employees.InsertOnSubmit(newEmployee);
//保存数据库的改变
employeeDB.SubmitChanges();
}
name.Text = "";
desc.Text = "";
}
else
{
MessageBox.Show("姓名和简介不能为空！");
}
}
/// <summary>
/// 编辑操作
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void editButton_Click(object sender, RoutedEventArgs e)
{
// 获取单击的按钮实例
var button = sender as Button;
if (button != null)
{
//获取当前按钮绑定的DataContext，即当前的编辑的EmployeeTable实例
EmployeeTable employeeForEdit = button.DataContext as EmployeeTable;
name.Text = employeeForEdit.EmployeeName;
desc.Text = employeeForEdit.EmployeeDesc;
//将需要编辑的表实例存储在State里面
State["employee"] = employeeForEdit;
employeeCol.EmployeeTables.Remove(employeeForEdit);
}
}
}
}运行效果如下：
