BinaryWriter::Write Method (array<Byte>^)


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Writes a byte array to the underlying stream.

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

virtual void Write(
	array<unsigned char>^ buffer


Type: array<System::Byte>^

A byte array containing the data to write.

Exception Condition

An I/O error occurs.


The stream is closed.


buffer is null.

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

The following code example shows how to write binary data using memory as a backing store, and then verify that the data was written correctly.

using namespace System;
using namespace System::IO;
int main()
   const int arrayLength = 1000;

   // Create random data to write to the stream.
   array<Byte>^dataArray = gcnew array<Byte>(arrayLength);
   (gcnew Random)->NextBytes( dataArray );
   BinaryWriter^ binWriter = gcnew BinaryWriter( gcnew MemoryStream );

   // Write the data to the stream.
   Console::WriteLine(  "Writing the data." );
   binWriter->Write( dataArray );

   // Create the reader using the stream from the writer.
   BinaryReader^ binReader = gcnew BinaryReader( binWriter->BaseStream );

   // Set the stream position to the beginning of the stream.
   binReader->BaseStream->Position = 0;

   // Read and verify the data.
   array<Byte>^verifyArray = binReader->ReadBytes( arrayLength );
   if ( verifyArray->Length != arrayLength )
      Console::WriteLine( "Error writing the data." );
      return  -1;

   for ( int i = 0; i < arrayLength; i++ )
      if ( verifyArray[ i ] != dataArray[ i ] )
         Console::WriteLine( "Error writing the data." );
         return  -1;

   Console::WriteLine( "The data was written and verified." );

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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