FileStream.EndWrite Method
Ends an asynchronous write operation and blocks until the I/O operation is complete. (Consider using WriteAsync instead; see the Remarks section.)
Namespace: System.IO
Assembly: mscorlib (in mscorlib.dll)
Parameters
- asyncResult
- Type: System.IAsyncResult
The pending asynchronous I/O request.
| Exception | Condition |
|---|---|
| ArgumentNullException | asyncResult is Nothing. |
| ArgumentException | This IAsyncResult object was not created by calling BeginWrite on this class. |
| InvalidOperationException | EndWrite is called multiple times. |
| IOException | The stream is closed or an internal error has occurred. |
In the .NET Framework 4 and earlier versions, you have to use methods such as BeginWrite and EndWrite to implement asynchronous file operations. These methods are still available in the .NET Framework 4.5 to support legacy code; however, the new async methods, such as ReadAsync, WriteAsync, CopyToAsync, and FlushAsync, help you implement asynchronous file operations more easily.
This method overrides EndWrite.
EndWrite must be called exactly once on every IAsyncResult from BeginWrite. EndWrite will block until the I/O operation has completed.
This code example is part of a larger example provided for the FileStream(String, FileMode, FileAccess, FileShare, Int32, Boolean) constructor.
Private Shared Sub EndWriteCallback(asyncResult As IAsyncResult) Dim tempState As State = _ DirectCast(asyncResult.AsyncState, State) Dim fStream As FileStream = tempState.FStream fStream.EndWrite(asyncResult) ' Asynchronously read back the written data. fStream.Position = 0 asyncResult = fStream.BeginRead( _ tempState.ReadArray, 0 , tempState.ReadArray.Length, _ AddressOf EndReadCallback, tempState) ' Concurrently do other work, such as ' logging the write operation. End Sub
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
