WindowsRuntimeStreamExtensions.AsInputStream(Stream) Método

Definição

Importante

Esta API não está em conformidade com CLS.

Converte um fluxo gerenciado no .NET para Aplicativos da Windows Store em um fluxo de entrada no Windows Runtime.Converts a managed stream in the .NET for Windows Store apps to an input stream in the Windows Runtime.

public:
[System::Runtime::CompilerServices::Extension]
 static Windows::Storage::Streams::IInputStream ^ AsInputStream(System::IO::Stream ^ stream);
[System.CLSCompliant(false)]
public static Windows.Storage.Streams.IInputStream AsInputStream (this System.IO.Stream stream);
static member AsInputStream : System.IO.Stream -> Windows.Storage.Streams.IInputStream

Parâmetros

stream
Stream

O fluxo a ser convertido.The stream to convert.

Retornos

Um objeto IInputStream do Windows Runtime que representa o fluxo convertido.A Windows Runtime IInputStream object that represents the converted stream.

Atributos

Exceções

stream é null.stream is null.

Não há suporte para leitura no fluxo.The stream does not support reading.

Exemplos

O exemplo a seguir mostra como usar os AsInputStream métodos AsOutputStream e para converter um fluxo gerenciado de e para um fluxo no Windows Runtime.The following example shows how to use the AsInputStream and AsOutputStream methods to convert a managed stream to and from a stream in the 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

Este é o código XAML associado ao exemplo anterior.Here's the XAML code that is associated with the previous example.

<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>

Comentários

Observação

Em Visual Basic e C#, você pode chamar esse método como um método de instância em qualquer objeto do Streamtipo.In Visual Basic and C#, you can call this method as an instance method on any object of type Stream. Quando você usar a sintaxe de método de instância para chamar esse método, omita o primeiro parâmetro.When you use instance method syntax to call this method, omit the first parameter. Para obter mais informações, consulte métodos de extensão (Visual Basic) ou métodosC# de extensão (guia de programação).For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

Aplica-se a