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.NET Framework Class Library
BinaryReaderRead Method

Reads characters from the underlying stream and advances the current position of the stream in accordance with the Encoding used and the specific character being read from the stream.

Namespace:   System.IO
Assembly:  mscorlib (in mscorlib.dll)
Syntax
Public Overridable Function Read As [%$TOPIC/493z3f6h_en-us_VS_110_1_0_0_0_0%]
public virtual [%$TOPIC/493z3f6h_en-us_VS_110_1_0_1_0_0%] Read()
public:
virtual [%$TOPIC/493z3f6h_en-us_VS_110_1_0_2_0_0%] Read()
abstract Read : unit -> [%$TOPIC/493z3f6h_en-us_VS_110_1_0_3_0_0%]  
override Read : unit -> [%$TOPIC/493z3f6h_en-us_VS_110_1_0_3_0_1%]

Return Value

Type: SystemInt32
The next character from the input stream, or -1 if no characters are currently available.
Exceptions
ExceptionCondition
IOException

An I/O error occurs.

ObjectDisposedException

The stream is closed.

Remarks

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

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

Examples

The following example shows how to read and write data using memory as a backing store. This example displays a list of invalid file path characters to the console. Although the code tries to display a list of all invalid file path characters, not all of the characters are within the displayable set of characters. Because the list of invalid characters can vary based on the system, output for this code may also vary.

Imports System
Imports System.IO

Public Class BinaryRW

    Shared Sub Main()

        Dim i As Integer = 0
        Dim invalidPathChars() As Char = Path.InvalidPathChars
        Dim memStream As new MemoryStream()
        Dim binWriter As New BinaryWriter(memStream)

        ' Write to memory.
        binWriter.Write("Invalid file path characters are: ")
        For i = 0 To invalidPathChars.Length - 1
            binWriter.Write(invalidPathChars(i))
        Next i

        ' Create the reader using the same MemoryStream  
        ' as used with the writer. 
        Dim binReader As New BinaryReader(memStream)

        ' Set Position to the beginning of the stream.
        memStream.Position = 0

        ' Read the data from memory and write it to the console.
        Console.Write(binReader.ReadString())
        Dim memoryData( _
            CInt(memStream.Length - memStream.Position) - 1) As Char 
        For i = 0 To memoryData.Length - 1
            memoryData(i) = Convert.ToChar(binReader.Read())
        Next i
        Console.WriteLine(memoryData)

	End Sub 
End Class
using System;
using System.IO;

class BinaryRW
{
    static void Main()
    {
        int i = 0;
        char[] invalidPathChars = Path.InvalidPathChars;
        MemoryStream memStream = new MemoryStream();
        BinaryWriter binWriter = new BinaryWriter(memStream);

        // Write to memory.
        binWriter.Write("Invalid file path characters are: ");
        for(i = 0; i < invalidPathChars.Length; i++)
        {
            binWriter.Write(invalidPathChars[i]);
        }

        // Create the reader using the same MemoryStream  
        // as used with the writer.
        BinaryReader binReader = new BinaryReader(memStream);

        // Set Position to the beginning of the stream.
        memStream.Position = 0;

        // Read the data from memory and write it to the console.
        Console.Write(binReader.ReadString());
        char[] memoryData = 
            new char[memStream.Length - memStream.Position];
        for(i = 0; i < memoryData.Length; i++)
        {
            memoryData[i] = Convert.ToChar(binReader.Read());
        }
        Console.WriteLine(memoryData);
    }
}
using namespace System;
using namespace System::IO;
int main()
{
   int i;
   array<Char>^invalidPathChars = Path::InvalidPathChars;
   MemoryStream^ memStream = gcnew MemoryStream;
   BinaryWriter^ binWriter = gcnew BinaryWriter( memStream );

   // Write to memory.
   binWriter->Write( "Invalid file path characters are: " );
   for ( i = 0; i < invalidPathChars->Length; i++ )
   {
      binWriter->Write( invalidPathChars[ i ] );

   }

   // Create the reader using the same MemoryStream  
   // as used with the writer.
   BinaryReader^ binReader = gcnew BinaryReader( memStream );

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

   // Read the data from memory and write it to the console.
   Console::Write( binReader->ReadString() );
   array<Char>^memoryData = gcnew array<Char>(memStream->Length - memStream->Position);
   for ( i = 0; i < memoryData->Length; i++ )
   {
      memoryData[ i ] = Convert::ToChar( binReader->Read() );

   }
   Console::WriteLine( memoryData );
}
Version Information

.NET Framework

Supported in: 4.5.2, 4.5.1, 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

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1
Platforms

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.