Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

public: virtual System::Threading::Tasks::Task ^ CopyToAsync(System::IO::Stream ^ destination, int bufferSize, System::Threading::CancellationToken cancellationToken);

public virtual System.Threading.Tasks.Task CopyToAsync(System.IO.Stream destination, int bufferSize, System.Threading.CancellationToken cancellationToken);

[System.Runtime.InteropServices.ComVisible(false)]public virtual System.Threading.Tasks.Task CopyToAsync(System.IO.Stream destination, int bufferSize, System.Threading.CancellationToken cancellationToken);

abstract member CopyToAsync : System.IO.Stream * int * System.Threading.CancellationToken -> System.Threading.Tasks.Taskoverride this.CopyToAsync : System.IO.Stream * int * System.Threading.CancellationToken -> System.Threading.Tasks.Task

[<System.Runtime.InteropServices.ComVisible(false)>]abstract member CopyToAsync : System.IO.Stream * int * System.Threading.CancellationToken -> System.Threading.Tasks.Taskoverride this.CopyToAsync : System.IO.Stream * int * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Overridable Function CopyToAsync (destination As Stream, bufferSize As Integer, cancellationToken As CancellationToken) As Task

Parameters

Returns

A task that represents the asynchronous copy operation.

Attributes

ComVisibleAttribute

Exceptions

Remarks

TheCopyToAsync method enables you to perform resource-intensive I/O operations without blocking the main thread. This performance consideration is particularly important in a Windows 8.x Store app or desktop app where a time-consuming stream operation can block the UI thread and make your app appear as if it is not working. The async methods are used in conjunction with theasync andawait keywords in Visual Basic and C#.

If the operation is canceled before it completes, the returned task contains theCanceled value for theStatus property.

Copying begins at the current position in the current stream.

For an example of copying between two streams, see theCopyToAsync(Stream) overload.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such asArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown byCopyTo(Stream, Int32).

Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

public: System::Threading::Tasks::Task ^ CopyToAsync(System::IO::Stream ^ destination, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task CopyToAsync(System.IO.Stream destination, System.Threading.CancellationToken cancellationToken);

member this.CopyToAsync : System.IO.Stream * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Function CopyToAsync (destination As Stream, cancellationToken As CancellationToken) As Task

Parameters

Returns

A task that represents the asynchronous copy operation.

Exceptions

Remarks

TheCopyToAsync method enables you to perform resource-intensive I/O operations without blocking the main thread. This performance consideration is particularly important in a Windows 8.x Store app or desktop app where a time-consuming stream operation can block the UI thread and make your app appear as if it is not working. The async methods are used in conjunction with theasync andawait keywords in Visual Basic and C#.

If the operation is canceled before it completes, the returned task contains theCanceled value for theStatus property.

Copying begins at the current position in the current stream.

For an example of copying between two streams, see theCopyToAsync(Stream) overload.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such asArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown byCopyTo(Stream).

Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

public: System::Threading::Tasks::Task ^ CopyToAsync(System::IO::Stream ^ destination);

public System.Threading.Tasks.Task CopyToAsync(System.IO.Stream destination);

[System.Runtime.InteropServices.ComVisible(false)]public System.Threading.Tasks.Task CopyToAsync(System.IO.Stream destination);

member this.CopyToAsync : System.IO.Stream -> System.Threading.Tasks.Task

[<System.Runtime.InteropServices.ComVisible(false)>]member this.CopyToAsync : System.IO.Stream -> System.Threading.Tasks.Task

Public Function CopyToAsync (destination As Stream) As Task

Parameters

Returns

A task that represents the asynchronous copy operation.

Attributes

ComVisibleAttribute

Exceptions

Examples

The following example demonstrates how to use twoFileStream objects to asynchronously copy the files from one directory to another. TheFileStream class derives from theStream class. Notice that theClick event handler for theButton control is marked with theasync modifier because it calls an asynchronous method

using System;using System.Threading.Tasks;using System.Windows;using System.IO;namespace WpfApplication{    public partial class MainWindow : Window    {        public MainWindow()        {            InitializeComponent();        }        private async void Button_Click(object sender, RoutedEventArgs e)        {            string StartDirectory = @"c:\Users\exampleuser\start";            string EndDirectory = @"c:\Users\exampleuser\end";            foreach (string filename in Directory.EnumerateFiles(StartDirectory))            {                using (FileStream SourceStream = File.Open(filename, FileMode.Open))                {                    using (FileStream DestinationStream = File.Create(EndDirectory + filename.Substring(filename.LastIndexOf('\\'))))                    {                        await SourceStream.CopyToAsync(DestinationStream);                    }                }            }        }    }}

Imports System.IOClass MainWindow    Private Async Sub Button_Click(sender As Object, e As RoutedEventArgs)        Dim StartDirectory As String = "c:\Users\exampleuser\start"        Dim EndDirectory As String = "c:\Users\exampleuser\end"        For Each filename As String In Directory.EnumerateFiles(StartDirectory)            Using SourceStream As FileStream = File.Open(filename, FileMode.Open)                Using DestinationStream As FileStream = File.Create(EndDirectory + filename.Substring(filename.LastIndexOf("\"c)))                    Await SourceStream.CopyToAsync(DestinationStream)                End Using            End Using        Next    End SubEnd Class

Remarks

TheCopyToAsync method enables you to perform resource-intensive I/O operations without blocking the main thread. This performance consideration is particularly important in a Windows 8.x Store app or desktop app where a time-consuming stream operation can block the UI thread and make your app appear as if it is not working. The async methods are used in conjunction with theasync andawait keywords in Visual Basic and C#.

Copying begins at the current position in the current stream.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such asArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown byCopyTo(Stream).

Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

Source:

Stream.cs

public: System::Threading::Tasks::Task ^ CopyToAsync(System::IO::Stream ^ destination, int bufferSize);

public System.Threading.Tasks.Task CopyToAsync(System.IO.Stream destination, int bufferSize);

[System.Runtime.InteropServices.ComVisible(false)]public System.Threading.Tasks.Task CopyToAsync(System.IO.Stream destination, int bufferSize);

member this.CopyToAsync : System.IO.Stream * int -> System.Threading.Tasks.Task

[<System.Runtime.InteropServices.ComVisible(false)>]member this.CopyToAsync : System.IO.Stream * int -> System.Threading.Tasks.Task

Public Function CopyToAsync (destination As Stream, bufferSize As Integer) As Task

Parameters

Returns

A task that represents the asynchronous copy operation.

Attributes

ComVisibleAttribute

Exceptions

Remarks

TheCopyToAsync method enables you to perform resource-intensive I/O operations without blocking the main thread. This performance consideration is particularly important in a Windows 8.x Store app or desktop app where a time-consuming stream operation can block the UI thread and make your app appear as if it is not working. The async methods are used in conjunction with theasync andawait keywords in Visual Basic and C#.

Copying begins at the current position in the current stream.

For an example of copying between two streams, see theCopyToAsync(Stream) overload.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such asArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown byCopyTo(Stream, Int32).