Xaml选择要保存文件的类型

前台代码:  

<Canvas Background="{StaticResource AppBarBackgroundThemeBrush}">

        <TextBox Name="txtContent"  Width="1365" Height="696" TextWrapping="Wrap" FontSize="18" Canvas.Top="1"/>

        <Button Content="保存到文件" Canvas.Left="710" FontSize="15"  Canvas.Top="702" Padding="25,17" Click="btnSave_Click" RenderTransformOrigin="-0.844,0.395" Height="60"/>

        <TextBlock Name="Msg" FontSize="20" Canvas.Left="1015"  Canvas.Top="722" RenderTransformOrigin="-1.207,0.583" />         <TextBox TextWrapping="Wrap" Text="支持多格保存文件，您可以写日记、Word、Txt等等...方便的用户的写作，快来体验吧" Canvas.Top="712" Width="574" Canvas.Left="10" Height="46"/>

    </Canvas>

</Page>

后台代码:

using System; using System.Collections.Generic; using System.IO; using System.Linq; 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.Storage;  using Windows.Storage.Pickers; 

// “空白页”项模板在 http://go.microsoft.com/fwlink/?LinkId=234238 上有介绍

namespace 选择保存文件 {     /// <summary>     /// 可用于自身或导航至 Frame 内部的空白页。     /// </summary>   public sealed partial class MainPage : Page       {           public MainPage()           {               this.InitializeComponent();           }                 private async void btnSave_Click(object sender, RoutedEventArgs e)           {               if (this.txtContent.Text.Equals(string.Empty))               {                   return;               }               FileSavePicker picker = new FileSavePicker();               // 提交按钮上显示的文本               picker.CommitButtonText = "保存";               // 支持的文件类型               picker.FileTypeChoices.Add("文本文件", new string[] { ".txt" });              picker.FileTypeChoices.Add("Word文档", new string[] { ".doc" });              picker.FileTypeChoices.Add("写字板", new string[] { ".rtf " });              picker.FileTypeChoices.Add("文档模板", new string[] { ".dot " });              picker.FileTypeChoices.Add("WPS", new string[] { ".wps " });              picker.FileTypeChoices.Add("Word平台", new string[] { ".wpt " });              picker.FileTypeChoices.Add("网页", new string[] { ".html " });              picker.FileTypeChoices.Add("数据", new string[] { ".data " });              picker.FileTypeChoices.Add("数据库", new string[] { ".dbf " });              picker.FileTypeChoices.Add("日记本", new string[] { ".jnt " });                           picker.FileTypeChoices.Add("可扩展标识语言", new string[] { ".xml" });  

             // 默认显示的目录               picker.SuggestedStartLocation = PickerLocationId.Desktop;               // 显示UI并返回内容               StorageFile file = await picker.PickSaveFileAsync();               // 向文件写入内容               if (file != null)               {                   await FileIO.WriteTextAsync(file, txtContent.Text, Windows.Storage.Streams.UnicodeEncoding.Utf8);                   this.Msg.Text = "文件已保存。";               }           }       }   }