EndWrite Method

Stream.EndWrite Method

Ends an asynchronous write operation.

Namespace: System.IO
Assembly: mscorlib (in mscorlib.dll)

public virtual void EndWrite (
	IAsyncResult asyncResult
public void EndWrite (
	IAsyncResult asyncResult
public function EndWrite (
	asyncResult : IAsyncResult
Not applicable.



A reference to the outstanding asynchronous I/O request.

Exception typeCondition


asyncResult is a null reference (Nothing in Visual Basic).


asyncResult did not originate from a BeginWrite method on the current stream.


The stream is closed or an internal error has occurred.

For an example of creating a file and writing text to a file, see Writing Text to a File. For an example of reading text from a file, see Reading Text from a File. For an example of reading from and writing to a binary file, see Reading and Writing to a Newly Created Data File. For an example of asynchronous file I/O, see Asynchronous File I/O.

EndWrite must be called exactly once on every IAsyncResult from BeginWrite.

This method blocks until the I/O operation has completed. Errors that occur during an asynchronous write request, such as a disk failure during the I/O request, occur on the thread pool thread and become visible upon a call to EndWrite. Exceptions thrown by the thread pool thread will not be visible when calling EndWrite.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0

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