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.NET Framework Class Library
BinaryWriterWrite Method (UInt64)

Writes an eight-byte unsigned integer to the current stream and advances the stream position by eight bytes.

This API is not CLS-compliant. 

Namespace:   System.IO
Assemblies:   mscorlib (in mscorlib.dll)
  System.IO (in System.IO.dll)
<[%$TOPIC/7c19y5s1_en-us_VS_110_1_0_0_0_0%](False)> _
Public Overridable Sub Write ( _
	value As [%$TOPIC/7c19y5s1_en-us_VS_110_1_0_0_0_1%] _
public virtual void Write(
	[%$TOPIC/7c19y5s1_en-us_VS_110_1_0_1_0_1%] value
virtual void Write(
	[%$TOPIC/7c19y5s1_en-us_VS_110_1_0_2_0_1%] value
abstract Write : 
        value:[%$TOPIC/7c19y5s1_en-us_VS_110_1_0_3_0_1%] -> unit 
override Write : 
        value:[%$TOPIC/7c19y5s1_en-us_VS_110_1_0_3_0_3%] -> unit


Type: SystemUInt64

The eight-byte unsigned integer to write.


An I/O error occurs.


The stream is closed.


BinaryWriter stores this data type in little endian format.

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.