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IsolatedStorageFileStream.BeginWrite Method

Begins an asynchronous write.

[Visual Basic]
Overrides Public Function BeginWrite( _
   ByVal buffer() As Byte, _
   ByVal offset As Integer, _
   ByVal numBytes As Integer, _
   ByVal userCallback As AsyncCallback, _
   ByVal stateObject As Object _
) As IAsyncResult
[C#]
public override IAsyncResult BeginWrite(
 byte[] buffer,
 int offset,
 int numBytes,
 AsyncCallback userCallback,
 object stateObject
);
[C++]
public: IAsyncResult* BeginWrite(
 unsigned char buffer __gc[],
 int offset,
 int numBytes,
 AsyncCallback* userCallback,
 Object* stateObject
);
[JScript]
public override function BeginWrite(
   buffer : Byte[],
 offset : int,
 numBytes : int,
 userCallback : AsyncCallback,
 stateObject : Object
) : IAsyncResult;

Parameters

buffer
The buffer to which to write data.
offset
The byte offset in array at which to begin writing.
numBytes
The maximum number of bytes to write.
userCallback
The method to be called when the asynchronous write operation is completed. This parameter is optional.
stateObject
The status of the asynchronous write.

Return Value

An IAsyncResult that represents the asynchronous write, which is possibly still pending. This IAsyncResult must be passed to this stream's EndWrite method to ensure that the write is complete, then frees resources appropriately. This can be done either by the same code that called BeginWrite or in a callback passed to BeginWrite.

Exceptions

Exception Type Condition
IOException An asynchronous write was attempted past the end of the file.

Remarks

If a IsolatedStorageFileStream is writable, writing at the end of the stream expands the stream.

The current position in the stream is updated when you issue the asynchronous read or write, not when the I/O operation completes.

You must call EndWrite with the IAsyncResult that this method returns to find out how many bytes were written.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

IsolatedStorageFileStream Class | IsolatedStorageFileStream Members | System.IO.IsolatedStorage Namespace

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