Flush Method
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Clears buffers for this stream and causes any buffered data to be written to the file.
Namespace: System.IO
Assembly: System.IO (in System.IO.dll)
Syntax
'Declaration
Public Overrides Sub Flush
public override void Flush()
public:
virtual void Flush() override
abstract Flush : unit -> unit
override Flush : unit -> unit
public override function Flush()
Remarks
A stream’s encoder is not flushed unless you explicitly call Flush or dispose of the object. Setting StreamWriter.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.
Because a buffer can be used for either reading or writing, Flush()()()() performs the following two functions:
Any data previously written to the buffer is copied to the file and the buffer is cleared except for its encoder state.
If BufferedStream.CanSeek is true and data was previously copied from the file to the buffer for reading, the current position within the file is decremented by the number of unread bytes in the buffer. The buffer is then cleared.
.NET Framework Security
- Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see dd66cd4c-b087-415f-9c3e-94e3a1835f74.