Stream.Write Method (System.IO)

Write Method

.NET Framework Class Library

Stream..::.Write Method

When overridden in a derived class, writes a sequence of bytes to the current stream and advances the current position within this stream by the number of bytes written.

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

Syntax

Visual Basic (Declaration)

Public MustOverride Sub Write ( _
    buffer As Byte(), _
    offset As Integer, _
    count As Integer _
)

Visual Basic (Usage)

Dim instance As Stream
Dim buffer As Byte()
Dim offset As Integer
Dim count As Integer

instance.Write(buffer, offset, count)

public abstract void Write(
    byte[] buffer,
    int offset,
    int count
)

Visual C++

public:
virtual void Write(
    array<unsigned char>^ buffer, 
    int offset, 
    int count
) abstract

JScript

public abstract function Write(
    buffer : byte[], 
    offset : int, 
    count : int
)

Parameters

buffer: Type: array<System..::.Byte>[]()[]
An array of bytes. This method copies count bytes from buffer to the current stream.

offset: Type: System..::.Int32
The zero-based byte offset in buffer at which to begin copying bytes to the current stream.

count: Type: System..::.Int32
The number of bytes to be written to the current stream.

Exceptions

Exception	Condition
ArgumentException	The sum of offset and count is greater than the buffer length.
ArgumentNullException	buffer is nullNothingnullptra null reference (Nothing in Visual Basic).
ArgumentOutOfRangeException	offset or count is negative.
IOException	An I/O error occurs.
NotSupportedException	The stream does not support writing.
ObjectDisposedException	Methods were called after the stream was closed.

Remarks

For an example of creating a file and writing text to a file, see How to: Write Text to a File. For an example of reading text from a file, see How to: Read Text from a File. For an example of reading from and writing to a binary file, see How to: Read and Write to a Newly Created Data File.

Use the CanWrite property to determine whether the current instance supports writing.

If the write operation is successful, the position within the stream advances by the number of bytes written. If an exception occurs, the position within the stream remains unchanged.

The default implementation calls the asynchronous BeginWrite method.

Examples

The following example demonstrates how to use the Write method to copy an input stream to an output stream.

Visual Basic

Const size As Integer = 4096
Dim bytes(4096) As Byte
Dim numBytes As Integer
numBytes = input.Read(bytes, 0, size)
While numBytes > 0
    output.Write(bytes, 0, numBytes)
    numBytes = input.Read(bytes, 0, size)
End While

const int size = 4096;
byte[] bytes = new byte[4096];
int numBytes;
while((numBytes = input.Read(bytes, 0, size)) > 0)
    output.Write(bytes, 0, numBytes);

Visual C++

const int size = 4096;
array<Byte>^ bytes = gcnew array<Byte>(4096);
int numBytes;
while ( (numBytes = input->Read( bytes, 0, size )) > 0 )
      output->Write( bytes, 0, numBytes );

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

Reference

Stream Class

Stream Members

System.IO Namespace

Other Resources

File and Stream I/O

How to: Read Text from a File

How to: Write Text to a File