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.NET Framework Class Library
BinaryReaderFillBuffer Method

Fills the internal buffer with the specified number of bytes read from the stream.

Namespace:   System.IO
Assemblies:   System.IO (in System.IO.dll)
  mscorlib (in mscorlib.dll)
Protected Overridable Sub FillBuffer ( _
	numBytes As [%$TOPIC/619hxhta_en-us_VS_110_1_0_0_0_0%] _
protected virtual void FillBuffer(
	[%$TOPIC/619hxhta_en-us_VS_110_1_0_1_0_0%] numBytes
virtual void FillBuffer(
	[%$TOPIC/619hxhta_en-us_VS_110_1_0_2_0_0%] numBytes
abstract FillBuffer : 
        numBytes:[%$TOPIC/619hxhta_en-us_VS_110_1_0_3_0_0%] -> unit  
override FillBuffer : 
        numBytes:[%$TOPIC/619hxhta_en-us_VS_110_1_0_3_0_1%] -> unit


Type: SystemInt32

The number of bytes to be read.


The end of the stream is reached before numBytes could be read.


An I/O error occurs.


Requested numBytes is larger than the internal buffer size.


The internal buffer size is the larger value between 16 and the value returned by GetMaxByteCount for the specified encoding.

For a list of common I/O tasks, see Common I/O Tasks.

Version Information

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, 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.