WindowsRuntimeStreamExtensions.AsOutputStream(Stream) Método

public:
[System::Runtime::CompilerServices::Extension]
 static Windows::Storage::Streams::IOutputStream ^ AsOutputStream(System::IO::Stream ^ stream);

[System.CLSCompliant(false)]
public static Windows.Storage.Streams.IOutputStream AsOutputStream(this System.IO.Stream stream);

[<System.CLSCompliant(false)>]
static member AsOutputStream : System.IO.Stream -> Windows.Storage.Streams.IOutputStream

<Extension()>
Public Function AsOutputStream (stream As Stream) As IOutputStream

Parâmetros

Retornos

Um objeto Windows Runtime Windows.Storage.Streams.IOutputStream que representa o fluxo convertido.

Atributos

CLSCompliantAttribute

Exceções

Exemplos

O exemplo a seguir mostra como usar os métodos AsInputStream e AsOutputStream> para converter um fluxo gerenciado de e para um fluxo no Windows Runtime.

using System;
using System.IO;
using System.Text;
using Windows.Storage;
using Windows.Storage.Streams;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Navigation;

namespace ExampleApplication
{
    public sealed partial class BlankPage : Page
    {
        System.Text.UnicodeEncoding ue;
        byte[] bytesToWrite;
        byte[] bytesToAdd;
        int totalBytes;

        public BlankPage()
        {
            this.InitializeComponent();
        }

        protected override void OnNavigatedTo(NavigationEventArgs e)
        {
            ue = new System.Text.UnicodeEncoding();
            bytesToWrite = ue.GetBytes("example text to write to memory stream");
            bytesToAdd = ue.GetBytes("text added through datawriter");
            totalBytes = bytesToWrite.Length + bytesToAdd.Length;
        }

        private async void CreateButton_Click(object sender, RoutedEventArgs e)
        {
            byte[] bytesRead = new byte[totalBytes];
            using (MemoryStream memStream = new MemoryStream(totalBytes))
            {
                await memStream.WriteAsync(bytesToWrite, 0, bytesToWrite.Length);

                DataWriter writer = new DataWriter(memStream.AsOutputStream());
                writer.WriteBytes(bytesToAdd);
                await writer.StoreAsync();

                memStream.Seek(0, SeekOrigin.Begin);

                DataReader reader = new DataReader(memStream.AsInputStream());
                await reader.LoadAsync((uint)totalBytes);
                reader.ReadBytes(bytesRead);
                Results.Text = ue.GetString(bytesRead, 0, bytesRead.Length);
            }
        }
    }
}

Imports Windows.Storage.Streams

Public NotInheritable Class BlankPage
    Inherits Page

    Dim ue As System.Text.UnicodeEncoding
    Dim bytesToWrite() As Byte
    Dim bytesToAdd() As Byte
    Dim totalBytes As Integer


    Protected Overrides Sub OnNavigatedTo(e As Navigation.NavigationEventArgs)
        ue = New System.Text.UnicodeEncoding()
        bytesToWrite = ue.GetBytes("example text to write to memory stream")
        bytesToAdd = ue.GetBytes("text added through datawriter")
        totalBytes = bytesToWrite.Length + bytesToAdd.Length
    End Sub

    Private Async Sub CreateButton_Click(sender As Object, e As RoutedEventArgs)
        Dim bytesRead(totalBytes - 1) As Byte
        Using memStream As MemoryStream = New MemoryStream(totalBytes)
            Await memStream.WriteAsync(bytesToWrite, 0, bytesToWrite.Length)

            Dim writer As DataWriter = New DataWriter(memStream.AsOutputStream())
            writer.WriteBytes(bytesToAdd)
            Await writer.StoreAsync()

            memStream.Seek(0, SeekOrigin.Begin)

            Dim reader As DataReader = New DataReader(memStream.AsInputStream())
            Await reader.LoadAsync(CType(totalBytes, UInteger))
            reader.ReadBytes(bytesRead)
            Results.Text = ue.GetString(bytesRead, 0, bytesRead.Length)
        End Using
    End Sub
End Class

Aqui está o código XAML associado ao exemplo anterior.

<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">
        <Button Name="CreateButton" Content="Write and read with stream" Click="CreateButton_Click"></Button>
        <TextBlock Name="Results"></TextBlock>
    </StackPanel>
</Page>

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