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.NET Framework Class Library
BinaryReaderReadChar Method

Reads the next character from the current 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
Assemblies:   System.IO (in System.IO.dll)
  mscorlib (in mscorlib.dll)
Syntax
Public Overridable Function ReadChar As [%$TOPIC/4aw416zk_en-us_VS_110_1_0_0_0_0%]
public virtual [%$TOPIC/4aw416zk_en-us_VS_110_1_0_1_0_0%] ReadChar()
public:
virtual [%$TOPIC/4aw416zk_en-us_VS_110_1_0_2_0_0%] ReadChar()
abstract ReadChar : unit -> [%$TOPIC/4aw416zk_en-us_VS_110_1_0_3_0_0%]  
override ReadChar : unit -> [%$TOPIC/4aw416zk_en-us_VS_110_1_0_3_0_1%]
public function ReadChar() : [%$TOPIC/4aw416zk_en-us_VS_110_1_0_4_0_0%]

Return Value

Type: SystemChar
A character read from the current stream.
Exceptions
ExceptionCondition
EndOfStreamException

The end of the stream is reached.

ObjectDisposedException

The stream is closed.

IOException

An I/O error occurs.

ArgumentException

A surrogate character was read.

Remarks

If the ReadChar method attempts to read a surrogate character in the stream an exception will be raised and the position in the stream will advance. The position is restored to the original location before ReadChar was called if the stream is seekable; however, if the stream is unseekable, the position will not be corrected. If surrogate characters can be expected in the stream, use the ReadChars method instead.

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.

Examples

The following code example shows how to read and write data using memory as a backing store.

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) = binReader.ReadChar()
        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] = binReader.ReadChar();
        }
        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 ] = binReader->ReadChar();

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

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

.NET for Windows Phone apps

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

Portable Class Library

Supported in: Portable Class Library