BinaryReader.ReadByte BinaryReader.ReadByte BinaryReader.ReadByte BinaryReader.ReadByte Method

Definition

Reads the next byte from the current stream and advances the current position of the stream by one byte.

public:
 virtual System::Byte ReadByte();
public virtual byte ReadByte ();
abstract member ReadByte : unit -> byte
override this.ReadByte : unit -> byte
Public Overridable Function ReadByte () As Byte

Returns

The next byte read from the current stream.

Exceptions

Examples

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()
{
   int i = 0;
   
   // Create random data to write to the stream.
   array<Byte>^writeArray = gcnew array<Byte>(1000);
   (gcnew Random)->NextBytes( writeArray );
   BinaryWriter^ binWriter = gcnew BinaryWriter( gcnew MemoryStream );
   BinaryReader^ binReader = gcnew BinaryReader( binWriter->BaseStream );
   try
   {
      
      // Write the data to the stream.
      Console::WriteLine( "Writing the data." );
      for ( i = 0; i < writeArray->Length; i++ )
      {
         binWriter->Write( writeArray[ i ] );

      }
      
      // Set the stream position to the beginning of the stream.
      binReader->BaseStream->Position = 0;
      
      // Read and verify the data from the stream.
      for ( i = 0; i < writeArray->Length; i++ )
      {
         if ( binReader->ReadByte() != writeArray[ i ] )
         {
            Console::WriteLine( "Error writing the data." );
            return  -1;
         }

      }
      Console::WriteLine( "The data was written and verified." );
   }
   // Catch the EndOfStreamException and write an error message.
   catch ( EndOfStreamException^ e ) 
   {
      Console::WriteLine( "Error writing the data.\n{0}", e->GetType()->Name );
   }

}

using System;
using System.IO;

class BinaryRW
{
    static void Main()
    {
        int i = 0;

        // Create random data to write to the stream.
        byte[] writeArray = new byte[1000];
        new Random().NextBytes(writeArray);

        BinaryWriter binWriter = new BinaryWriter(new MemoryStream());
        BinaryReader binReader = 
            new BinaryReader(binWriter.BaseStream);

        try
        {
            // Write the data to the stream.
            Console.WriteLine("Writing the data.");
            for(i = 0; i < writeArray.Length; i++)
            {
                binWriter.Write(writeArray[i]);
            }

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

            // Read and verify the data from the stream.
            for(i = 0; i < writeArray.Length; i++)
            {
                if(binReader.ReadByte() != writeArray[i])
                {
                    Console.WriteLine("Error writing the data.");
                    return;
                }
            }
            Console.WriteLine("The data was written and verified.");
        }

        // Catch the EndOfStreamException and write an error message.
        catch(EndOfStreamException e)
        {
            Console.WriteLine("Error writing the data.\n{0}",
                e.GetType().Name);
        }
    }
}
Imports System
Imports System.IO

Public Class BinaryRW

    Shared Sub Main()
    
        Dim i As Integer = 0

        ' Create random data to write to the stream.
        Dim writeArray(1000) As Byte
        Dim randomGenerator As New Random()
        randomGenerator.NextBytes(writeArray)

        Dim binWriter As New BinaryWriter(New MemoryStream())
        Dim binReader As New BinaryReader(binWriter.BaseStream)

        Try
        
            ' Write the data to the stream.
            Console.WriteLine("Writing the data.")
            For i = 0 To writeArray.Length - 1
                binWriter.Write(writeArray(i))
            Next i

            ' Set the stream position to the beginning of the stream.
            binReader.BaseStream.Position = 0

            ' Read and verify the data from the stream.
            For i = 0 To writeArray.Length - 1
                If binReader.ReadByte() <> writeArray(i) Then
                    Console.WriteLine("Error writing the data.")
                    Return
                End If
            Next i
            Console.WriteLine("The data was written and verified.")

        ' Catch the EndOfStreamException and write an error message.
        Catch ex As EndOfStreamException
            Console.WriteLine("Error writing the data: {0}", _
                ex.GetType().Name)
        End Try
    
    End Sub
End Class

Remarks

BinaryReader does not restore the file position after an unsuccessful read.

Because of data formatting conflicts, using this method with the following encodings is not recommended:

  • UTF-7

  • ISO-2022-JP

  • ISCII

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

Applies to

See also