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BitConverter.ToDouble Método

Definição

Sobrecargas

ToDouble(ReadOnlySpan<Byte>)

Converte um intervalo de bytes somente leitura em um valor de ponto flutuante de precisão dupla.

ToDouble(Byte[], Int32)

Retorna um número de ponto flutuante de precisão dupla convertido de oito bytes em uma posição especificada em uma matriz de bytes.

ToDouble(ReadOnlySpan<Byte>)

Converte um intervalo de bytes somente leitura em um valor de ponto flutuante de precisão dupla.

public:
 static double ToDouble(ReadOnlySpan<System::Byte> value);
public static double ToDouble (ReadOnlySpan<byte> value);
static member ToDouble : ReadOnlySpan<byte> -> double
Public Shared Function ToDouble (value As ReadOnlySpan(Of Byte)) As Double

Parâmetros

value
ReadOnlySpan<Byte>

Um intervalo somente leitura que contém os bytes a serem convertidos.

Retornos

Double

Um valor de ponto flutuante de precisão dupla que representa os bytes convertidos.

Exceções

O tamanho de value é menor que o tamanho de um valor de Double.

Aplica-se a

ToDouble(Byte[], Int32)

Retorna um número de ponto flutuante de precisão dupla convertido de oito bytes em uma posição especificada em uma matriz de bytes.

public:
 static double ToDouble(cli::array <System::Byte> ^ value, int startIndex);
public static double ToDouble (byte[] value, int startIndex);
static member ToDouble : byte[] * int -> double
Public Shared Function ToDouble (value As Byte(), startIndex As Integer) As Double

Parâmetros

value
Byte[]

Uma matriz de bytes que inclui os oito bytes a serem convertidos.

startIndex
Int32

A posição inicial dentro de value.

Retornos

Double

Um número de ponto flutuante de precisão dupla formado por oito bytes começando em startIndex.

Exceções

startIndex é maior ou igual ao tamanho de value menos 7 e é menor ou igual ao tamanho de value menos 1.

value é null.

startIndex é menor que zero ou maior que o tamanho de value menos 1.

Exemplos

O exemplo de código a seguir converte elementos de Byte matrizes em Double valores com o ToDouble método.

// Example of the BitConverter::ToDouble method.
using namespace System;

// Convert eight byte array elements to a double and display it.
void BAToDouble( array<unsigned char>^bytes, int index )
{
   double value = BitConverter::ToDouble( bytes, index );
   Console::WriteLine( "{0,5}{1,27}{2,27:E16}", index, BitConverter::ToString( bytes, index, 8 ), value );
}


// Display a byte array, using multiple lines if necessary.
void WriteMultiLineByteArray( array<unsigned char>^bytes )
{
   const int rowSize = 20;
   int iter;
   Console::WriteLine( "initial unsigned char array" );
   Console::WriteLine( "---------------------------" );
   for ( iter = 0; iter < bytes->Length - rowSize; iter += rowSize )
   {
      Console::Write( BitConverter::ToString( bytes, iter, rowSize ) );
      Console::WriteLine( "-" );

   }
   Console::WriteLine( BitConverter::ToString( bytes, iter ) );
   Console::WriteLine();
}

int main()
{
   array<unsigned char>^byteArray = {0,0,0,0,0,0,0,0,240,63,0,0,0,0,0,224,111,64,0,0,224,255,255,255,239,65,0,0,0,0,0,0,112,63,0,0,0,0,0,0,240,61,223,136,30,28,254,116,170,1,250,89,140,66,202,192,243,63,251,89,140,66,202,192,243,63,252,89,140,66,202,192,243,63,82,211,187,188,232,126,61,126,255,255,255,255,255,255,239,255,255,255,255,255,255,239,127,1,0,0,0,0,0,0,0,248,255,0,0,0,0,0,0,240,255,0,0,0,0,0,0,240,127};
   Console::WriteLine( "This example of the BitConverter::ToDouble( unsigned "
   "char[ ], int ) \nmethod generates the following output. It "
   "converts elements of a \nbyte array to double values.\n" );
   WriteMultiLineByteArray( byteArray );
   Console::WriteLine( "{0,5}{1,27}{2,27:E16}", "index", "array elements", "double" );
   Console::WriteLine( "{0,5}{1,27}{2,27:E16}", "-----", "--------------", "------" );
   
   // Convert byte array elements to double values.
   BAToDouble( byteArray, 0 );
   BAToDouble( byteArray, 2 );
   BAToDouble( byteArray, 10 );
   BAToDouble( byteArray, 18 );
   BAToDouble( byteArray, 26 );
   BAToDouble( byteArray, 34 );
   BAToDouble( byteArray, 42 );
   BAToDouble( byteArray, 50 );
   BAToDouble( byteArray, 58 );
   BAToDouble( byteArray, 66 );
   BAToDouble( byteArray, 74 );
   BAToDouble( byteArray, 82 );
   BAToDouble( byteArray, 89 );
   BAToDouble( byteArray, 97 );
   BAToDouble( byteArray, 99 );
   BAToDouble( byteArray, 107 );
   BAToDouble( byteArray, 115 );
}

/*
This example of the BitConverter.ToDouble( byte( ), int )
method generates the following output. It converts elements
of a byte array to double values.

initial byte array
------------------
00-00-00-00-00-00-00-00-F0-3F-00-00-00-00-00-E0-6F-40-00-00-
E0-FF-FF-FF-EF-41-00-00-00-00-00-00-70-3F-00-00-00-00-00-00-
F0-3D-DF-88-1E-1C-FE-74-AA-01-FA-59-8C-42-CA-C0-F3-3F-FB-59-
8C-42-CA-C0-F3-3F-FC-59-8C-42-CA-C0-F3-3F-52-D3-BB-BC-E8-7E-
3D-7E-FF-FF-FF-FF-FF-FF-EF-FF-FF-FF-FF-FF-FF-EF-7F-01-00-00-
00-00-00-00-00-F8-FF-00-00-00-00-00-00-F0-FF-00-00-00-00-00-
00-F0-7F

index             array elements                     double
-----             --------------                     ------
    0    00-00-00-00-00-00-00-00    0.0000000000000000E+000
    2    00-00-00-00-00-00-F0-3F    1.0000000000000000E+000
   10    00-00-00-00-00-E0-6F-40    2.5500000000000000E+002
   18    00-00-E0-FF-FF-FF-EF-41    4.2949672950000000E+009
   26    00-00-00-00-00-00-70-3F    3.9062500000000000E-003
   34    00-00-00-00-00-00-F0-3D    2.3283064365386963E-010
   42    DF-88-1E-1C-FE-74-AA-01    1.2345678901234500E-300
   50    FA-59-8C-42-CA-C0-F3-3F    1.2345678901234565E+000
   58    FB-59-8C-42-CA-C0-F3-3F    1.2345678901234567E+000
   66    FC-59-8C-42-CA-C0-F3-3F    1.2345678901234569E+000
   74    52-D3-BB-BC-E8-7E-3D-7E    1.2345678901234569E+300
   82    FF-FF-FF-FF-FF-FF-EF-FF   -1.7976931348623157E+308
   89    FF-FF-FF-FF-FF-FF-EF-7F    1.7976931348623157E+308
   97    01-00-00-00-00-00-00-00    4.9406564584124654E-324
   99    00-00-00-00-00-00-F8-FF                        NaN
  107    00-00-00-00-00-00-F0-FF                  -Infinity
  115    00-00-00-00-00-00-F0-7F                   Infinity
*/
// Example of the BitConverter.ToDouble method.
using System;

class BytesToDoubleDemo
{
    const string formatter = "{0,5}{1,27}{2,27:E16}";

    // Convert eight byte array elements to a double and display it.
    public static void BAToDouble( byte[ ] bytes, int index )
    {
        double value = BitConverter.ToDouble( bytes, index );

        Console.WriteLine( formatter, index,
            BitConverter.ToString( bytes, index, 8 ), value );
    }

    // Display a byte array, using multiple lines if necessary.
    public static void WriteMultiLineByteArray( byte[ ] bytes )
    {
        const int rowSize = 20;
        int iter;

        Console.WriteLine( "initial byte array" );
        Console.WriteLine( "------------------" );

        for( iter = 0; iter < bytes.Length - rowSize; iter += rowSize )
        {
            Console.Write(
                BitConverter.ToString( bytes, iter, rowSize ) );
            Console.WriteLine( "-" );
        }

        Console.WriteLine( BitConverter.ToString( bytes, iter ) );
        Console.WriteLine( );
    }

    public static void Main( )
    {
        byte[ ] byteArray = {
              0,   0,   0,   0,   0,   0,   0,   0, 240,  63,
              0,   0,   0,   0,   0, 224, 111,  64,   0,   0,
            224, 255, 255, 255, 239,  65,   0,   0,   0,   0,
              0,   0, 112,  63,   0,   0,   0,   0,   0,   0,
            240,  61, 223, 136,  30,  28, 254, 116, 170,   1,
            250,  89, 140,  66, 202, 192, 243,  63, 251,  89,
            140,  66, 202, 192, 243,  63, 252,  89, 140,  66,
            202, 192, 243,  63,  82, 211, 187, 188, 232, 126,
             61, 126, 255, 255, 255, 255, 255, 255, 239, 255,
            255, 255, 255, 255, 255, 239, 127,   1,   0,   0,
              0,   0,   0,   0,   0, 248, 255,   0,   0,   0,
              0,   0,   0, 240, 255,   0,   0,   0,   0,   0,
              0, 240, 127 };

        Console.WriteLine(
            "This example of the BitConverter.ToDouble( byte[ ], " +
            "int ) \nmethod generates the following output. It " +
            "converts elements \nof a byte array to double values.\n" );

        WriteMultiLineByteArray( byteArray );

        Console.WriteLine( formatter, "index", "array elements",
            "double" );
        Console.WriteLine( formatter, "-----", "--------------",
            "------" );

        // Convert byte array elements to double values.
        BAToDouble( byteArray, 0 );
        BAToDouble( byteArray, 2 );
        BAToDouble( byteArray, 10 );
        BAToDouble( byteArray, 18 );
        BAToDouble( byteArray, 26 );
        BAToDouble( byteArray, 34 );
        BAToDouble( byteArray, 42 );
        BAToDouble( byteArray, 50 );
        BAToDouble( byteArray, 58 );
        BAToDouble( byteArray, 66 );
        BAToDouble( byteArray, 74 );
        BAToDouble( byteArray, 82 );
        BAToDouble( byteArray, 89 );
        BAToDouble( byteArray, 97 );
        BAToDouble( byteArray, 99 );
        BAToDouble( byteArray, 107 );
        BAToDouble( byteArray, 115 );
    }
}

/*
This example of the BitConverter.ToDouble( byte[ ], int )
method generates the following output. It converts elements
of a byte array to double values.

initial byte array
------------------
00-00-00-00-00-00-00-00-F0-3F-00-00-00-00-00-E0-6F-40-00-00-
E0-FF-FF-FF-EF-41-00-00-00-00-00-00-70-3F-00-00-00-00-00-00-
F0-3D-DF-88-1E-1C-FE-74-AA-01-FA-59-8C-42-CA-C0-F3-3F-FB-59-
8C-42-CA-C0-F3-3F-FC-59-8C-42-CA-C0-F3-3F-52-D3-BB-BC-E8-7E-
3D-7E-FF-FF-FF-FF-FF-FF-EF-FF-FF-FF-FF-FF-FF-EF-7F-01-00-00-
00-00-00-00-00-F8-FF-00-00-00-00-00-00-F0-FF-00-00-00-00-00-
00-F0-7F

index             array elements                     double
-----             --------------                     ------
    0    00-00-00-00-00-00-00-00    0.0000000000000000E+000
    2    00-00-00-00-00-00-F0-3F    1.0000000000000000E+000
   10    00-00-00-00-00-E0-6F-40    2.5500000000000000E+002
   18    00-00-E0-FF-FF-FF-EF-41    4.2949672950000000E+009
   26    00-00-00-00-00-00-70-3F    3.9062500000000000E-003
   34    00-00-00-00-00-00-F0-3D    2.3283064365386963E-010
   42    DF-88-1E-1C-FE-74-AA-01    1.2345678901234500E-300
   50    FA-59-8C-42-CA-C0-F3-3F    1.2345678901234565E+000
   58    FB-59-8C-42-CA-C0-F3-3F    1.2345678901234567E+000
   66    FC-59-8C-42-CA-C0-F3-3F    1.2345678901234569E+000
   74    52-D3-BB-BC-E8-7E-3D-7E    1.2345678901234569E+300
   82    FF-FF-FF-FF-FF-FF-EF-FF   -1.7976931348623157E+308
   89    FF-FF-FF-FF-FF-FF-EF-7F    1.7976931348623157E+308
   97    01-00-00-00-00-00-00-00    4.9406564584124654E-324
   99    00-00-00-00-00-00-F8-FF                        NaN
  107    00-00-00-00-00-00-F0-FF                  -Infinity
  115    00-00-00-00-00-00-F0-7F                   Infinity
*/
open System

let print obj1 obj2 obj3 = printfn $"{obj1,5}{obj2,27}{obj3,27:E16}"

// Convert eight byte array elements to a double and display it.
let BAToDouble bytes index =
    let value = BitConverter.ToDouble(bytes, index)

    print index (BitConverter.ToString(bytes, index, 8)) value

// Display a byte array, using multiple lines if necessary.
let writeMultiLineByteArray (bytes: byte []) =
    let rowSize = 20

    printfn "initial byte array"
    printfn "------------------"

    let mutable iter = 0
    for i in 0 .. rowSize .. (bytes.Length - rowSize - 1) do
        printfn $"{BitConverter.ToString(bytes, iter, rowSize)}-"
        iter <- i

    printfn $"{BitConverter.ToString(bytes, iter + rowSize)}\n"

let byteArray =
    [| 0uy; 0uy; 0uy; 0uy; 0uy; 0uy; 0uy; 0uy; 240uy; 63uy
       0uy; 0uy; 0uy; 0uy; 0uy; 224uy; 111uy; 64uy; 0uy; 0uy;
       224uy; 255uy; 255uy; 255uy; 239uy; 65uy; 0uy; 0uy; 0uy; 0uy
       0uy; 0uy; 112uy; 63uy; 0uy; 0uy; 0uy; 0uy; 0uy; 0uy
       240uy; 61uy; 223uy; 136uy; 30uy; 28uy; 254uy; 116uy; 170uy; 1uy
       250uy; 89uy; 140uy; 66uy; 202uy; 192uy; 243uy; 63uy; 251uy; 89uy
       140uy; 66uy; 202uy; 192uy; 243uy; 63uy; 252uy; 89uy; 140uy; 66uy
       202uy; 192uy; 243uy; 63uy; 82uy; 211uy; 187uy; 188uy; 232uy; 126uy
       61uy; 126uy; 255uy; 255uy; 255uy; 255uy; 255uy; 255uy; 239uy; 255uy
       255uy; 255uy; 255uy; 255uy; 255uy; 239uy; 127uy; 1uy; 0uy; 0uy
       0uy; 0uy; 0uy; 0uy; 0uy; 248uy; 255uy; 0uy; 0uy; 0uy
       0uy; 0uy; 0uy; 240uy; 255uy; 0uy; 0uy; 0uy; 0uy; 0uy
       0uy; 240uy; 127uy |]

printfn "This example of the BitConverter.ToDouble(byte [], int) \nmethod generates the following output. It converts elements \nof a byte array to double values.\n"

writeMultiLineByteArray byteArray

print "index" "array elements" "double"
print "-----" "--------------" "------"

// Convert byte array elements to double values.
BAToDouble byteArray 0
BAToDouble byteArray 2
BAToDouble byteArray 10
BAToDouble byteArray 18
BAToDouble byteArray 26
BAToDouble byteArray 34
BAToDouble byteArray 42
BAToDouble byteArray 50
BAToDouble byteArray 58
BAToDouble byteArray 66
BAToDouble byteArray 74
BAToDouble byteArray 82
BAToDouble byteArray 89
BAToDouble byteArray 97
BAToDouble byteArray 99
BAToDouble byteArray 107
BAToDouble byteArray 115


// This example of the BitConverter.ToDouble(byte [], int )
// method generates the following output. It converts elements
// of a byte array to double values.

// initial byte array
// ------------------
// 00-00-00-00-00-00-00-00-F0-3F-00-00-00-00-00-E0-6F-40-00-00-
// 00-00-00-00-00-00-00-00-F0-3F-00-00-00-00-00-E0-6F-40-00-00-
// E0-FF-FF-FF-EF-41-00-00-00-00-00-00-70-3F-00-00-00-00-00-00-
// F0-3D-DF-88-1E-1C-FE-74-AA-01-FA-59-8C-42-CA-C0-F3-3F-FB-59-
// 8C-42-CA-C0-F3-3F-FC-59-8C-42-CA-C0-F3-3F-52-D3-BB-BC-E8-7E-
// 3D-7E-FF-FF-FF-FF-FF-FF-EF-FF-FF-FF-FF-FF-FF-EF-7F-01-00-00-
// 00-F0-7F
//
// index             array elements                     double
// -----             --------------                     ------
//     0    00-00-00-00-00-00-00-00    0.0000000000000000E+000
//     2    00-00-00-00-00-00-F0-3F    1.0000000000000000E+000
//    10    00-00-00-00-00-E0-6F-40    2.5500000000000000E+002
//    18    00-00-E0-FF-FF-FF-EF-41    4.2949672950000000E+009
//    26    00-00-00-00-00-00-70-3F    3.9062500000000000E-003
//    34    00-00-00-00-00-00-F0-3D    2.3283064365386963E-010
//    42    DF-88-1E-1C-FE-74-AA-01    1.2345678901234500E-300
//    50    FA-59-8C-42-CA-C0-F3-3F    1.2345678901234565E+000
//    58    FB-59-8C-42-CA-C0-F3-3F    1.2345678901234567E+000
//    66    FC-59-8C-42-CA-C0-F3-3F    1.2345678901234569E+000
//    74    52-D3-BB-BC-E8-7E-3D-7E    1.2345678901234569E+300
//    82    FF-FF-FF-FF-FF-FF-EF-FF   -1.7976931348623157E+308
//    89    FF-FF-FF-FF-FF-FF-EF-7F    1.7976931348623157E+308
//    97    01-00-00-00-00-00-00-00    4.9406564584124654E-324
//    99    00-00-00-00-00-00-F8-FF                        NaN
//   107    00-00-00-00-00-00-F0-FF                         -∞
//   115    00-00-00-00-00-00-F0-7F                          ∞
' Example of the BitConverter.ToDouble method.
Module BytesToDoubleDemo

    Const formatter As String = "{0,5}{1,27}{2,27:E16}"
 
    ' Convert eight Byte array elements to a Double and display it.
    Sub BAToDouble( bytes( ) As Byte, index As Integer )

        Dim value As Double = BitConverter.ToDouble( bytes, index )

        Console.WriteLine( formatter, index, _
            BitConverter.ToString( bytes, index, 8 ), value )
    End Sub 

    ' Display a Byte array, using multiple lines if necessary.
    Sub WriteMultiLineByteArray( bytes( ) As Byte )
       
        Const rowSize As Integer = 20 
        Dim iter As Integer

        Console.WriteLine( "initial Byte array" )
        Console.WriteLine( "------------------" )

        For iter = 0 To bytes.Length - rowSize - 1 Step rowSize
            Console.Write( _
                BitConverter.ToString( bytes, iter, rowSize ) )
            Console.WriteLine( "-" )
        Next iter

        Console.WriteLine( BitConverter.ToString( bytes, iter ) )
        Console.WriteLine( )
    End Sub

    Sub Main( )
        Dim byteArray as Byte( ) = { _
              0,   0,   0,   0,   0,   0,   0,   0, 240,  63, _
              0,   0,   0,   0,   0, 224, 111,  64,   0,   0, _
            224, 255, 255, 255, 239,  65,   0,   0,   0,   0, _
              0,   0, 112,  63,   0,   0,   0,   0,   0,   0, _
            240,  61, 223, 136,  30,  28, 254, 116, 170,   1, _
            250,  89, 140,  66, 202, 192, 243,  63, 251,  89, _
            140,  66, 202, 192, 243,  63, 252,  89, 140,  66, _
            202, 192, 243,  63,  82, 211, 187, 188, 232, 126, _
             61, 126, 255, 255, 255, 255, 255, 255, 239, 255, _
            255, 255, 255, 255, 255, 239, 127,   1,   0,   0, _
              0,   0,   0,   0,   0, 248, 255,   0,   0,   0, _
              0,   0,   0, 240, 255,   0,   0,   0,   0,   0, _
              0, 240, 127 }

        Console.WriteLine( _
            "This example of the BitConverter.ToDouble( Byte( ), " & _
            "Integer ) " & vbCrLf & "method generates the " & _
            "following output. It converts elements " & vbCrLf & _
            "of a Byte array to Double values." & vbCrLf )

        WriteMultiLineByteArray( byteArray )

        Console.WriteLine( formatter, "index", "array elements", _
            "Double" )
        Console.WriteLine( formatter, "-----", "--------------", _
            "------" )
          
        ' Convert Byte array elements to Double values.
        BAToDouble( byteArray, 0 )
        BAToDouble( byteArray, 2 )
        BAToDouble( byteArray, 10 )
        BAToDouble( byteArray, 18 )
        BAToDouble( byteArray, 26 )
        BAToDouble( byteArray, 34 )
        BAToDouble( byteArray, 42 )
        BAToDouble( byteArray, 50 )
        BAToDouble( byteArray, 58 )
        BAToDouble( byteArray, 66 )
        BAToDouble( byteArray, 74 )
        BAToDouble( byteArray, 82 )
        BAToDouble( byteArray, 89 )
        BAToDouble( byteArray, 97 )
        BAToDouble( byteArray, 99 )
        BAToDouble( byteArray, 107 )
        BAToDouble( byteArray, 115 )
    End Sub 
End Module

' This example of the BitConverter.ToDouble( Byte( ), Integer )
' method generates the following output. It converts elements
' of a Byte array to Double values.
' 
' initial Byte array
' ------------------
' 00-00-00-00-00-00-00-00-F0-3F-00-00-00-00-00-E0-6F-40-00-00-
' E0-FF-FF-FF-EF-41-00-00-00-00-00-00-70-3F-00-00-00-00-00-00-
' F0-3D-DF-88-1E-1C-FE-74-AA-01-FA-59-8C-42-CA-C0-F3-3F-FB-59-
' 8C-42-CA-C0-F3-3F-FC-59-8C-42-CA-C0-F3-3F-52-D3-BB-BC-E8-7E-
' 3D-7E-FF-FF-FF-FF-FF-FF-EF-FF-FF-FF-FF-FF-FF-EF-7F-01-00-00-
' 00-00-00-00-00-F8-FF-00-00-00-00-00-00-F0-FF-00-00-00-00-00-
' 00-F0-7F
' 
' index             array elements                     Double
' -----             --------------                     ------
'     0    00-00-00-00-00-00-00-00    0.0000000000000000E+000
'     2    00-00-00-00-00-00-F0-3F    1.0000000000000000E+000
'    10    00-00-00-00-00-E0-6F-40    2.5500000000000000E+002
'    18    00-00-E0-FF-FF-FF-EF-41    4.2949672950000000E+009
'    26    00-00-00-00-00-00-70-3F    3.9062500000000000E-003
'    34    00-00-00-00-00-00-F0-3D    2.3283064365386963E-010
'    42    DF-88-1E-1C-FE-74-AA-01    1.2345678901234500E-300
'    50    FA-59-8C-42-CA-C0-F3-3F    1.2345678901234565E+000
'    58    FB-59-8C-42-CA-C0-F3-3F    1.2345678901234567E+000
'    66    FC-59-8C-42-CA-C0-F3-3F    1.2345678901234569E+000
'    74    52-D3-BB-BC-E8-7E-3D-7E    1.2345678901234569E+300
'    82    FF-FF-FF-FF-FF-FF-EF-FF   -1.7976931348623157E+308
'    89    FF-FF-FF-FF-FF-FF-EF-7F    1.7976931348623157E+308
'    97    01-00-00-00-00-00-00-00    4.9406564584124654E-324
'    99    00-00-00-00-00-00-F8-FF                        NaN
'   107    00-00-00-00-00-00-F0-FF                  -Infinity
'   115    00-00-00-00-00-00-F0-7F                   Infinity

Comentários

O ToDouble método converte os bytes do índice startIndex em startIndex + 7 em um Double valor. A ordem dos bytes na matriz deve refletir a endianidade da arquitetura do sistema de computador. Para obter mais informações, consulte a seção Comentários do tópico de BitConverter classe.

Confira também

Aplica-se a