刚刚做过这类开发，所以就先献丑了，当然所贴上的源代码都是经过验证过的，已经执行成功了，希望能够给大家一些借鉴：

以下是metro UI代码：

<Page

    x:Class="Camera.MainPage"

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

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

    xmlns:local="using:Camera"

    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"

    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

    mc:Ignorable="d">

    <Grid Background="{ThemeResource ApplicationPageBackgroundThemeBrush}">

        <Button x:Name="btnCamera" Content="打开摄像头" HorizontalAlignment="Left" Margin="48,259,0,0" VerticalAlignment="Top" Click="btnCamera_Click" Height="45"/>

        <Image x:Name="img1" HorizontalAlignment="Left" Height="609" Margin="240,78,0,0" VerticalAlignment="Top" Width="718" Stretch="Fill"/>

        <Button x:Name="btnSave" Content="保存图片" HorizontalAlignment="Left" Margin="48,369,0,0" VerticalAlignment="Top" Height="44" Click="btnSave_Click"/>

    </Grid>

</Page>

显示的界面事实上非常easy，可是这不重要，功能才是基本的，以下贴上基本的开发代码：

using System;

using System.Collections.Generic;

using System.IO;

using System.Linq;

using System.Runtime.InteropServices.WindowsRuntime;

using Windows.Foundation;

using Windows.Foundation.Collections;

using Windows.UI.Xaml;

using Windows.UI.Xaml.Controls;

using Windows.UI.Xaml.Controls.Primitives;

using Windows.UI.Xaml.Data;

using Windows.UI.Xaml.Input;

using Windows.UI.Xaml.Media;

using Windows.UI.Xaml.Navigation;

using Windows.Media.Capture;

using Windows.Storage;

using Windows.Storage.Pickers;

using Windows.UI.Xaml.Media.Imaging;

using Windows.Storage.Streams;

// The Blank Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=234238

/*

 *

 * 作者：李天鹏

 * 功能：调用PC上自带的camera实现拍照的功能，并保存在对应的目录下

 * */

namespace Camera

{

    /// <summary>

    /// An empty page that can be used on its own or navigated to within a Frame.

    /// </summary>

    public sealed partial class MainPage : Page

    {

        private StorageFile file = null;

        public MainPage()

        {

            this.InitializeComponent();

        }

        private async void btnCamera_Click(object sender, RoutedEventArgs e)

        {

            CameraCaptureUI dialog = new CameraCaptureUI();

            dialog.PhotoSettings.CroppedAspectRatio = new Size(16, 9);

            file = await dialog.CaptureFileAsync(CameraCaptureUIMode.Photo);

            if (file != null)

            {

                BitmapImage bitmapImage = new BitmapImage();

                using (IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read))

                {

                    bitmapImage.SetSource(fileStream);

                }

                img1.Source = bitmapImage;

            }

        }

        private async void btnSave_Click(object sender, RoutedEventArgs e)

        {

            if (img1.Source == null)

                return;

            else

            {

                FileSavePicker picker = new FileSavePicker();

                picker.CommitButtonText = "保存";

                picker.SuggestedFileName = "hello";

                picker.FileTypeChoices.Add("图片",new string[]{".jpg",".jpeg",".bmp",".png"});

                picker.SuggestedStartLocation = PickerLocationId.PicturesLibrary;

                StorageFile filePath = await picker.PickSaveFileAsync();

                if (filePath != null)

                {

                    //打开通过摄像头拍摄的照片，并返回流，以流的形式读取文件

                    var streamRandom = await file.OpenAsync(FileAccessMode.Read);

                    //将拍摄的照片以流的形式读取到缓冲区

                    IBuffer buffer = RandomAccessStreamToBuffer(streamRandom);

                    //将缓冲区内容写入对应的目录中

                    await FileIO.WriteBufferAsync(filePath, buffer);

                }

            }

        }

        //将图片写入到缓冲区

        private IBuffer RandomAccessStreamToBuffer(IRandomAccessStream randomstream)

        {

            Stream stream = WindowsRuntimeStreamExtensions.AsStreamForRead(randomstream.GetInputStreamAt(0));

            MemoryStream memoryStream = new MemoryStream();

            if (stream != null)

            {

                byte[] bytes = ConvertStreamTobyte(stream);  //将流转化为字节型数组

                if (bytes != null)

                {

                    var binaryWriter = new BinaryWriter(memoryStream);

                    binaryWriter.Write(bytes);

                }

            }

            IBuffer buffer = WindowsRuntimeBufferExtensions.GetWindowsRuntimeBuffer(memoryStream, 0, (int)memoryStream.Length);

            return buffer;

        }

        //将流转换成二进制

        public static byte[] ConvertStreamTobyte(Stream input)

        {

            byte[] buffer = new byte[16 * 1024];

            using (MemoryStream ms = new MemoryStream())

            {

                int read;

                while ((read = input.Read(buffer, 0, buffer.Length)) > 0)

                {

                    ms.Write(buffer, 0, read);

                }

                return ms.ToArray();

            }

        }

    }

}

可是这还不够，假设须要调用camera，还须要一些权限，应该在Package.appxmanifest里面改动权限，

改动例如以下：仅仅要勾上webcam即可了。

源代码下载：

http://download.csdn.net/detail/litianpeng1991/7548065