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StreamWriter.AutoFlush Property

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Gets or sets a value indicating whether the StreamWriter will flush its buffer to the underlying stream after every call to StreamWriter.Write.

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

Syntax

'Declaration
Public Overridable Property AutoFlush As Boolean
public virtual bool AutoFlush { get; set; }

Property Value

Type: System.Boolean
true to force StreamWriter to flush its buffer; otherwise, false.

Remarks

Flushing the stream will not flush its underlying encoder unless you explicitly call Flush or Close. Setting AutoFlush to true means that data will be flushed from the buffer to the stream, but the encoder state will not be flushed. This allows the encoder to keep its state (partial characters) so that it can encode the next block of characters correctly. This scenario affects UTF8 and UTF7 where certain characters can only be encoded after the encoder receives the adjacent character or characters.

When AutoFlush is set to false, StreamWriter will do a limited amount of buffering, both internally and potentially in the encoder from the encoding you passed in. You can get better performance by setting AutoFlush to false, assuming that you always call Close (or at least Flush) when you're done writing with a StreamWriter.

For example, set AutoFlush to true when you are writing to a device where the user expects immediate feedback. Console.Out is one of these cases: The StreamWriter used internally for writing to Console flushes all its internal state except the encoder state after every call to StreamWriter.Write.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.