WindowsRuntimeStorageExtensions 類別

定義

public ref class WindowsRuntimeStorageExtensions abstract sealed

[System.Security.SecurityCritical]
public static class WindowsRuntimeStorageExtensions

[<System.Security.SecurityCritical>]
type WindowsRuntimeStorageExtensions = class

Public Module WindowsRuntimeStorageExtensions

繼承

Object

WindowsRuntimeStorageExtensions

屬性

SecurityCriticalAttribute

範例

以下範例展示了如何在 Windows Store 應用程式中以 Stream 開啟應用程式資料中的檔案，並透過 StreamWriter 類別的實例來寫入。 接著它會利用類別的 StreamReader 實例讀取檔案內容。

using System;
using System.IO;
using Windows.Storage;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

namespace ExampleApplication
{
    public sealed partial class BlankPage : Page
    {
        public BlankPage()
        {
            this.InitializeComponent();
        }

        private async void CreateButton_Click(object sender, RoutedEventArgs e)
        {
            using (StreamWriter writer =
                new StreamWriter(await ApplicationData.Current.LocalFolder.OpenStreamForWriteAsync(
                "testfile.txt",  CreationCollisionOption.OpenIfExists)))
            {
                await writer.WriteLineAsync("new entry");
                await writer.WriteLineAsync(UserText.Text);
            }
        }

        private async void VerifyButton_Click(object sender, RoutedEventArgs e)
        {
            StorageFile openedFile = await ApplicationData.Current.LocalFolder.GetFileAsync("testfile.txt");
            using (StreamReader reader = new StreamReader(await openedFile.OpenStreamForReadAsync()))
            {
                Results.Text = await reader.ReadToEndAsync();
            }
        }
    }
}

Imports System.IO
Imports Windows.Storage

NotInheritable Public Class BlankPage
    Inherits Page

    Private Async Sub CreateButton_Click(sender As Object, e As RoutedEventArgs)
        Using writer As StreamWriter =
               New StreamWriter(Await ApplicationData.Current.LocalFolder.OpenStreamForWriteAsync(
               "testfile.txt", CreationCollisionOption.OpenIfExists))
            Await writer.WriteLineAsync("new entry")
            Await writer.WriteLineAsync(UserText.Text)
        End Using
    End Sub

    Private Async Sub VerifyButton_Click(sender As Object, e As RoutedEventArgs)
        Dim openedFile As StorageFile = Await ApplicationData.Current.LocalFolder.GetFileAsync("testfile.txt")
        Using reader As StreamReader = New StreamReader(Await openedFile.OpenStreamForReadAsync())
            Results.Text = Await reader.ReadToEndAsync()
        End Using
    End Sub
End Class

下一個範例展示了與前一個範例相關的 XAML 程式碼。

<Page
    x:Class="ExampleApplication.BlankPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:ExampleApplication"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d">

    <StackPanel Background="{StaticResource ApplicationPageBackgroundBrush}" VerticalAlignment="Center" HorizontalAlignment="Center">
        <TextBlock Text="Provide text to write to file:"></TextBlock>
        <TextBox Name="UserText" Width="400"></TextBox>
        <Button Name="CreateButton" Content="Create File" Click="CreateButton_Click"></Button>
        <Button Name="VerifyButton" Content="Verify Contents" Click="VerifyButton_Click"></Button>
        <TextBlock Name="Results"></TextBlock>
    </StackPanel>
</Page>

備註

這些擴充功能方法只在開發 Windows 商店應用程式時使用。 這些方法提供了方便地開啟檔案以在 Windows 商店應用程式中閱讀或寫入的管道。 你不需要建立該類別的實例WindowsRuntimeStorageExtensions;而是從 和 <xref:Windows.Storage.IStorageFile> 介面的實例<xref:Windows.Storage.IStorageFolder>中使用這些方法。

該 WindowsRuntimeStorageExtensions 類別包含兩種可擴展 <xref:Windows.Storage.IStorageFile> 用於讀取或寫入的方法：

• OpenStreamForReadAsync(IStorageFile)
• OpenStreamForWriteAsync(IStorageFile)

WindowsRuntimeStorageExtensions 類別包含兩種可擴充 <xref:Windows.Storage.IStorageFolder> 讀寫的方法：

• OpenStreamForReadAsync(IStorageFolder, String)
• OpenStreamForWriteAsync(IStorageFolder, String, CreationCollisionOption)