自学WP7第一个例子：时钟

<phone:PhoneApplicationPage 
    x:Class="Clock.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">

    <!--LayoutRoot is the root grid where all page content is placed-->
    <Grid x:Name="LayoutRoot" Background="Transparent">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <!--TitlePanel contains the name of the application and page title-->
        <StackPanel x:Name="TitlePanel" Grid.Row="0" Margin="12,17,0,28">
            <TextBlock x:Name="ApplicationTitle" Text="Wilson" Style="{StaticResource PhoneTextNormalStyle}"/>
            <TextBlock x:Name="PageTitle" Text="Clock" Margin="9,-7,0,0" Style="{StaticResource PhoneTextTitle1Style}"/>
        </StackPanel>

        <!--ContentPanel - place additional content here-->
        <Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
            <Canvas Width="444" Height="444" x:Name="cvClock"/>
        </Grid>
    </Grid>
 
    <!--Sample code showing usage of ApplicationBar-->
    <!--<phone:PhoneApplicationPage.ApplicationBar>
        <shell:ApplicationBar IsVisible="True" IsMenuEnabled="True">
            <shell:ApplicationBarIconButton IconUri="/Images/appbar_button1.png" Text="Button 1"/>
            <shell:ApplicationBarIconButton IconUri="/Images/appbar_button2.png" Text="Button 2"/>
            <shell:ApplicationBar.MenuItems>
                <shell:ApplicationBarMenuItem Text="MenuItem 1"/>
                <shell:ApplicationBarMenuItem Text="MenuItem 2"/>
            </shell:ApplicationBar.MenuItems>
        </shell:ApplicationBar>
    </phone:PhoneApplicationPage.ApplicationBar>-->

</phone:PhoneApplicationPage>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using Microsoft.Phone.Controls;
using System.Windows.Threading;

namespace Clock
{
    public partial class MainPage : PhoneApplicationPage
    {
        // Constructor
        public MainPage()
        {
            InitializeComponent();           
            SetClock();   //设置时钟

        }

        private void SetClock()
        {
            DispatcherTimer dtr = new DispatcherTimer();
            dtr.Interval = TimeSpan.FromSeconds(1);
            dtr.Tick += new EventHandler(MyDial);
            dtr.Start();
        }

        private void MyDial(object sender, EventArgs e)
        {
            int count = 60;
            cvClock.Children.Clear();

            TextBlock tbSec = new TextBlock();   //秒针
            TextBlock tbMin = new TextBlock();   //分针
            TextBlock tbHour = new TextBlock();  //时间

            DateTime dt = DateTime.Now;
            
            double secAngle = dt.Second * (360 / 60);   //秒针偏移角度
            double minAngle = dt.Minute * (360 / 60) + secAngle / 60;   //分针偏移角度
            double hourAngle = (dt.Hour % 12) * (360 / 12) + minAngle / 12;   //时针偏移角度

            AddClockHands(tbSec, "-------------------->", secAngle);
            AddClockHands(tbMin, "------------------>", minAngle);
            AddClockHands(tbHour, "--------------->", hourAngle);

            
            string dialText = string.Empty;
            double dialAngle;

            for (int i = 0; i < count; i++)
            {
                dialAngle = i * (360 / count);
                
                TextBlock tb = new TextBlock();                
                tb.TextAlignment = TextAlignment.Right;               

                if (i % 5 == 0)
                {
                    dialText = "—";                   
                    tb.Foreground = new SolidColorBrush(Colors.Green);
                }
                else
                {                   
                    dialText = "-";
                }               

                AddClockHands(tb, dialText, dialAngle);
            }
        }

        ///<summary>
        /// 添加表盘、秒针、分针、时针
        ///</summary>
        ///<param name="tb"></param>
        ///<param name="text"></param>
        ///<param name="angle"></param>
        public void AddClockHands(TextBlock tb, string text, double angle)
        {
            tb.Text = text;
            tb.Width = 180;
            Canvas.SetLeft(tb, 222);
            Canvas.SetTop(tb, 222);
            tb.RenderTransformOrigin = new Point(0, 0);
            RotateTransform rt = new RotateTransform();
            rt.CenterX = (tb.ActualHeight) / 2;
            rt.CenterY = (tb.ActualHeight) / 2;

            rt.Angle = angle - 90;
            tb.RenderTransform = rt;

            cvClock.Children.Add(tb);
        }
    }
}