BinaryReader.ReadByte メソッド

定義

名前空間:

System.IO

アセンブリ:

System.Runtime.dll

ソース:

BinaryReader.cs

現在のストリームから次のバイトを読み取り、ストリームの現在位置を 1 バイトだけ進めます。

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

戻り値

Byte

現在のストリームから読み取った次のバイト。

例外

EndOfStreamException

ストリームの末尾に到達しました。

ObjectDisposedException

ストリームは閉じられています。

IOException

I/O エラーが発生しました。

例

次のコード例は、メモリをバッキング ストアとして使用してバイナリ データを書き込み、データが正しく書き込まれたことを確認する方法を示しています。

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);
        }
    }
}

open System
open System.IO

// Create random data to write to the stream.
let writeArray = Array.zeroCreate<byte> 1000
Random().NextBytes writeArray

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

try
    // Write the data to the stream.
    printfn "Writing the data."
    for i = 0 to writeArray.Length - 1 do
        binWriter.Write writeArray[i]

    // Set the stream position to the beginning of the stream.
    binReader.BaseStream.Position <- 0

    let mutable failed = false
    // Read and verify the data from the stream.
    for i = 0 to writeArray.Length - 1 do
        if binReader.ReadByte() <> writeArray[i] then
            printfn "Error writing the data."
            failed <- true
    if not failed then
        printfn "The data was written and verified."

// Catch the EndOfStreamException and write an error message.
with :? EndOfStreamException as e ->
    printfn $"Error writing the data.\n{e.GetType().Name}"

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

注釈

BinaryReader は、読み取りが失敗した後にファイルの位置を復元しません。

データの書式設定が競合するため、次のエンコードでこのメソッドを使用することはお勧めしません。

• UTF-7

• ISO-2022-JP

• ISCII

共通 I/O タスクの一覧は、 共通 I/O タスク を参照してください。

こちらもご覧ください

• ファイルおよびストリーム入出力
• 方法: ファイルからのテキストの読み取り
• 方法: テキストのファイルへの書き込み