BinaryReader.ReadBytes(Int32) 메서드

정의

현재 스트림에서 지정된 바이트 수만큼 바이트 배열로 읽어 오고 현재 위치를 해당 바이트 수만큼 앞으로 이동합니다.Reads the specified number of bytes from the current stream into a byte array and advances the current position by that number of bytes.

public:
 virtual cli::array <System::Byte> ^ ReadBytes(int count);
public virtual byte[] ReadBytes (int count);
abstract member ReadBytes : int -> byte[]
override this.ReadBytes : int -> byte[]
Public Overridable Function ReadBytes (count As Integer) As Byte()

매개 변수

count
Int32

읽을 바이트 수입니다.The number of bytes to read. 이 값은 0 또는 음수가 아닌 숫자여야 합니다. 그렇지 않으면 예외가 발생합니다.This value must be 0 or a non-negative number or an exception will occur.

반환

Byte[]

내부 스트림에서 읽은 데이터를 포함하는 바이트 배열입니다.A byte array containing data read from the underlying stream. 이 바이트 배열은 스트림의 끝에 도달할 경우 요청된 바이트 수보다 작을 수 있습니다.This might be less than the number of bytes requested if the end of the stream is reached.

예외

읽을 수 있도록 디코딩된 문자의 수는 count보다 큽니다.The number of decoded characters to read is greater than count. 유니코드 디코더가 대체 문자 또는 서로게이트 쌍을 반환하는 경우 이 문제가 발생할 수 있습니다.This can happen if a Unicode decoder returns fallback characters or a surrogate pair.

I/O 오류가 발생했습니다.An I/O error occurred.

스트림이 닫혔습니다.The stream is closed.

count가 음수입니다.count is negative.

예제

다음 코드 예제에는 메모리를 사용 하 여 백업 저장소로 이진 데이터를 쓰고 다음 데이터 쓰여졌는지 확인 하는 방법을 보여 줍니다.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." );
}

using System;
using System.IO;

class BinaryRW
{
    static void Main()
    {
        const int arrayLength = 1000;

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

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

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

        // Read and verify the data.
        byte[] verifyArray = binReader.ReadBytes(arrayLength);
        if(verifyArray.Length != arrayLength)
        {
            Console.WriteLine("Error writing the data.");
            return;
        }
        for(int i = 0; i < arrayLength; i++)
        {
            if(verifyArray[i] != dataArray[i])
            {
                Console.WriteLine("Error writing the data.");
                return;
            }
        }
        Console.WriteLine("The data was written and verified.");
    }
}
Imports System.IO

Public Class BinaryRW

    Shared Sub Main()
    
        Const upperBound As Integer = 1000

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

        Dim binWriter As New BinaryWriter(New MemoryStream())

        ' Write the data to the stream.
        Console.WriteLine("Writing the data.")
        binWriter.Write(dataArray)

        ' Create the reader using the stream from the writer.
        Dim binReader As New BinaryReader(binWriter.BaseStream)

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

        ' Read and verify the data.
        Dim verifyArray() As Byte = _
            binReader.ReadBytes(dataArray.Length)
        If verifyArray.Length <> dataArray.Length Then
            Console.WriteLine("Error writing the data.")
            Return
        End If
        For i As Integer = 0 To upperBound
            If verifyArray(i) <> dataArray(i) Then
                Console.WriteLine("Error writing the data.")
                Return
            End If
        Next i
        Console.WriteLine("The data was written and verified.")
    
    End Sub
End Class

이 예제에서는 파일의 내용을 읽고 덤프 텍스트로 콘솔에 표시 합니다.This example reads the contents of a file and displays it to the console as dump text. 읽는 중인 파일의 끝에서 검색 된 경우의 길이 Byte 에서 반환 된 배열 ReadBytes 0.The end of the file that is being read is detected when the length of the Byte array returned from ReadBytes is zero.

using System;
using System.IO;
using System.Text;

public class DumpFileSample
{
    private static readonly int CHUNK_SIZE = 1024;
    public static void Main(String[] args)
    {
        if ((args.Length == 0) || !File.Exists(args[0]))
        {
            Console.WriteLine("Please provide an existing file name.");
        }
        else
        {
            using (FileStream fs = new FileStream(args[0], FileMode.Open, FileAccess.Read))
            {
                using (BinaryReader br = new BinaryReader(fs, new ASCIIEncoding()))
                {
                    byte[] chunk;

                    chunk = br.ReadBytes(CHUNK_SIZE);
                    while(chunk.Length > 0)
                    {
                        DumpBytes(chunk, chunk.Length);
                        chunk = br.ReadBytes(CHUNK_SIZE);
                    }
                }
            }
        }
    }

    public static void DumpBytes(byte[] bdata, int len)
    {
        int i;
        int j = 0;
        char dchar;
        // 3 * 16 chars for hex display, 16 chars for text and 8 chars
        // for the 'gutter' int the middle.
        StringBuilder dumptext = new StringBuilder("        ", 16 * 4 + 8);
        for (i = 0; i < len; i++)
        {
            dumptext.Insert(j * 3, String.Format("{0:X2} ", (int)bdata[i]));
            dchar = (char)bdata[i];
            //' replace 'non-printable' chars with a '.'.
            if (Char.IsWhiteSpace(dchar) || Char.IsControl(dchar))
            {
                dchar = '.';
            }
            dumptext.Append(dchar);
            j++;
            if (j == 16)
            {
                Console.WriteLine(dumptext);
                dumptext.Length = 0;
                dumptext.Append("        ");
                j = 0;
            }
        }
        // display the remaining line
        if (j > 0)
        {
            for (i = j; i < 16; i++)
            {
                dumptext.Insert(j * 3, "   ");
            }
            Console.WriteLine(dumptext);
        }
    }
}
Imports System.IO
Imports System.Text

Module Module1
    Private ReadOnly CHUNK_SIZE As Integer = 1024
    Public Sub Main(args() As String)
        If ((args.Length = 0) OrElse Not File.Exists(args(0))) Then
            Console.WriteLine("Please provide an existing file name.")
        Else
            Using fs As FileStream = New FileStream(args(0), FileMode.Open, FileAccess.Read)
                Using br As New BinaryReader(fs, New ASCIIEncoding())
                    Dim chunk(CHUNK_SIZE) As Byte
                    chunk = br.ReadBytes(CHUNK_SIZE)

                    While chunk.Length > 0
                        DumpBytes(chunk, chunk.Length)
                        chunk = br.ReadBytes(CHUNK_SIZE)
                    End While
                End Using
            End Using
        End If
    End Sub

    Public Sub DumpBytes(bdata() As Byte, len As Integer)
        Dim i As Integer
        Dim j As Integer = 0
        Dim dchar As Char
        ' 3 * 16 chars for hex display, 16 chars for text and 8 chars
        ' for the 'gutter' int the middle.
        Dim dumptext As New StringBuilder("        ", 16 * 4 + 8)
        For i = 0 To len - 1
            dumptext.Insert(j * 3, String.Format("{0:X2} ", CType(bdata(i), Integer)))
            dchar = Convert.ToChar(bdata(i))
            ' replace 'non-printable' chars with a '.'.
            If Char.IsWhiteSpace(dchar) Or Char.IsControl(dchar) Then
                dchar = "."
            End If
            dumptext.Append(dchar)
            j += 1
            If j = 16 Then
                Console.WriteLine(dumptext)
                dumptext.Length = 0
                dumptext.Append("        ")
                j = 0
            End If
        Next i
        ' display the remaining line
        If j > 0 Then
            ' add blank hex spots to align the 'gutter'.
            For i = j To 15
                dumptext.Insert(j * 3, "   ")
            Next i
            Console.WriteLine(dumptext)
        End If
    End Sub

End Module

설명

BinaryReader 읽기 작업에 실패 한 후에 파일 위치를 복원 하지 않습니다.BinaryReader does not restore the file position after an unsuccessful read operation.

공통적인 I/O 작업의 목록을 참조 하세요 공통적인 I/O 작업합니다.For a list of common I/O tasks, see Common I/O Tasks.

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