BinaryReader.ReadDouble BinaryReader.ReadDouble BinaryReader.ReadDouble BinaryReader.ReadDouble Method

정의

현재 스트림에서 8바이트 부동 소수점 값을 읽고 스트림의 현재 위치를 8바이트 앞으로 이동합니다.Reads an 8-byte floating point value from the current stream and advances the current position of the stream by eight bytes.

public:
 virtual double ReadDouble();
public virtual double ReadDouble ();
abstract member ReadDouble : unit -> double
override this.ReadDouble : unit -> double
Public Overridable Function ReadDouble () As Double

반환

현재 스트림에서 읽은 8바이트 부동 소수점 값입니다.An 8-byte floating point value read from the current stream.

예외

스트림의 끝에 도달한 경우The end of the stream is reached.

I/O 오류가 발생했습니다.An I/O error occurs.

예제

다음 코드 예제에는 읽기 및 쓰기는 방법을 보여 줍니다 Double 를 사용 하 여 메모리 데이터를 BinaryReaderBinaryWriter 의 맨 위에 있는 클래스는 MemoryStream 클래스.The following code example shows how to read and write Double data to memory by using the BinaryReader and BinaryWriter classes on top of the MemoryStream class. MemoryStream 읽기 및 쓰기만 Byte 데이터입니다.MemoryStream only reads and writes Byte data.

using namespace System;
using namespace System::IO;
int main()
{
   int i;
   const int arrayLength = 1000;
   
   // Create random data to write to the stream.
   array<double>^dataArray = gcnew array<double>(arrayLength);
   Random^ randomGenerator = gcnew Random;
   for ( i = 0; i < arrayLength; i++ )
   {
      dataArray[ i ] = 100.1 * randomGenerator->NextDouble();

   }
   BinaryWriter^ binWriter = gcnew BinaryWriter( gcnew MemoryStream );
   try
   {
      
      // Write data to the stream.
      Console::WriteLine( "Writing data to the stream." );
      i = 0;
      for ( i = 0; i < arrayLength; i++ )
      {
         binWriter->Write( dataArray[ i ] );

      }
      
      // Create a reader using the stream from the writer.
      BinaryReader^ binReader = gcnew BinaryReader( binWriter->BaseStream );
      
      // Return to the beginning of the stream.
      binReader->BaseStream->Position = 0;
      try
      {
         
         // Read and verify the data.
         i = 0;
         Console::WriteLine( "Verifying the written data." );
         for ( i = 0; i < arrayLength; i++ )
         {
            if ( binReader->ReadDouble() != dataArray[ i ] )
            {
               Console::WriteLine( "Error writing data." );
               break;
            }

         }
         Console::WriteLine( "The data was written and verified." );
      }
      catch ( EndOfStreamException^ e ) 
      {
         Console::WriteLine( "Error writing data: {0}.", e->GetType()->Name );
      }

   }
   finally
   {
      binWriter->Close();
   }

}

using System;
using System.IO;

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

        // Create random data to write to the stream.
        Random randomGenerator = new Random();
        double[] dataArray = new double[arrayLength];
        for(i = 0; i < arrayLength; i++)
        {
            dataArray[i] = 100.1 * randomGenerator.NextDouble();
        }

        using(BinaryWriter binWriter = 
            new BinaryWriter(new MemoryStream()))
        {
            // Write the data to the stream.
            Console.WriteLine("Writing data to the stream.");
            for(i = 0; i < arrayLength; i++)
            {
                binWriter.Write(dataArray[i]);
            }

            // Create a reader using the stream from the writer.
            using(BinaryReader binReader = 
                new BinaryReader(binWriter.BaseStream))
            {
                try
                {
                    // Return to the beginning of the stream.
                    binReader.BaseStream.Position = 0;

                    // Read and verify the data.
                    Console.WriteLine("Verifying the written data.");
                    for(i = 0; i < arrayLength; i++)
                    {
                        if(binReader.ReadDouble() != dataArray[i])
                        {
                            Console.WriteLine("Error writing data.");
                            break;
                        }
                    }
                    Console.WriteLine("The data was written " +
                        "and verified.");
                }
                catch(EndOfStreamException e)
                {
                    Console.WriteLine("Error writing data: {0}.",
                        e.GetType().Name);
                }
            }
        }
    }
}
Imports System.IO

Public Class BinaryRW

    Shared Sub Main()
    
        Dim i As Integer
        Const upperBound As Integer = 1000

        ' Create random data to write to the stream.
        Dim dataArray(upperBound) As Double
        Dim randomGenerator As New Random()
        For i = 0 To upperBound
            dataArray(i) = 100.1 * randomGenerator.NextDouble()
        Next i

        Dim binWriter As New BinaryWriter(New MemoryStream())
        Try

            ' Write data to the stream.
            Console.WriteLine("Writing data to the stream.")
            
            For i = 0 To upperBound
                binWriter.Write(dataArray(i))
            Next i

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

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

            ' Read and verify the data.
            Try
                Console.WriteLine("Verifying the written data.")
                For i = 0 To upperBound
                    If binReader.ReadDouble() <> dataArray(i) Then
                        Console.WriteLine("Error writing data.")
                        Exit For
                    End If
                Next i
                Console.WriteLine("The data was written and verified.")
            Catch ex As EndOfStreamException
                Console.WriteLine("Error writing data: {0}.", _
                    ex.GetType().Name)
            End Try
        Finally
            binWriter.Close()
        End Try

    End Sub
End Class

설명

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

BinaryReader 이 데이터 형식은 little endian 형식으로 읽습니다.BinaryReader reads this data type in little-endian format.

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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