<Window x:Class="WpfApplication1.MainWindow"

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

        Title="MainWindow" Height="350" Width="525">

    <Grid>

        <Button Name="b1" Width="100" Height="20" Click="b1_Click"></Button>

        <Button Name="b2" Width="100" Height="20" Margin="0,50,0,0" Click="b2_Click"></Button>

        <Frame Name="f1" NavigationUIVisibility="Hidden" />

    </Grid>

</Window>

<Window x:Class="WpfApplication1.MainWindow"

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

        Title="MainWindow" Height="350" Width="525">

    <Grid>

        <Frame Name="f1" NavigationUIVisibility="Hidden">

            <Frame.Content>

                <Grid>

                    <Button Name="b1" Width="100" Height="20" Click="b1_Click"></Button>

                    <Button Name="b2" Width="100" Height="20" Margin="0,50,0,0" Click="b2_Click"></Button>

                </Grid>

            </Frame.Content>

        </Frame>

    </Grid>

</Window>

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Data;

using System.Windows.Documents;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Imaging;

using System.Windows.Navigation;

using System.Windows.Shapes;

namespace WpfApplication1

{

    /// <summary>

    /// MainWindow.xaml 的交互逻辑

    /// </summary>

    public partial class MainWindow : Window

    {

        Page1 p1;

        Page2 p2;

        public MainWindow()

        {

            InitializeComponent();

            p1 = new Page1();

            p2 = new Page2();

        }

        private void b1_Click(object sender, RoutedEventArgs e)

        {

            //f1.Source = new Uri("Page1.xaml", UriKind.Relative);

            f1.Content = p1;

        }

        private void b2_Click(object sender, RoutedEventArgs e)

        {

            //f1.Source = new Uri("Page2.xaml", UriKind.Relative);

            f1.Content = p2;

        }

    }

}