共用方式為


BitConverter.ToSingle 方法

定義

多載

ToSingle(ReadOnlySpan<Byte>)

將唯讀位元組範圍轉換成單精確度浮點值。

ToSingle(Byte[], Int32)

傳回從位元組陣列中指定位置的四個位元組所轉換的單精確度浮點數。

ToSingle(ReadOnlySpan<Byte>)

來源:
BitConverter.cs
來源:
BitConverter.cs
來源:
BitConverter.cs

將唯讀位元組範圍轉換成單精確度浮點值。

public:
 static float ToSingle(ReadOnlySpan<System::Byte> value);
public static float ToSingle (ReadOnlySpan<byte> value);
static member ToSingle : ReadOnlySpan<byte> -> single
Public Shared Function ToSingle (value As ReadOnlySpan(Of Byte)) As Single

參數

value
ReadOnlySpan<Byte>

包含要轉換之位元組的唯讀範圍。

傳回

單精確度浮點值,表示已轉換的位元組。

例外狀況

value 的長度小於 Single 值的長度。

適用於

ToSingle(Byte[], Int32)

來源:
BitConverter.cs
來源:
BitConverter.cs
來源:
BitConverter.cs

傳回從位元組陣列中指定位置的四個位元組所轉換的單精確度浮點數。

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

參數

value
Byte[]

位元組陣列。

startIndex
Int32

開始位置在 value 內。

傳回

由四個位元組所形成的單精確度浮點數開始於 startIndex

例外狀況

startIndex 大於或等於 value 的長度減去 3,而且小於或等於 value 的長度減去 1。

valuenull

startIndex 小於零或大於 value 的長度減去 1。

範例

下列程式碼範例會使用 ToSingle 方法,將陣列的專案 Byte 轉換為 Single 值。

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

// Convert four byte array elements to a float and display it.
void BAToSingle( array<unsigned char>^bytes, int index )
{
   float value = BitConverter::ToSingle( bytes, index );
   Console::WriteLine( "{0,5}{1,17}{2,18:E7}", index, BitConverter::ToString( bytes, index, 4 ), 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 = {0,0,0,0,128,63,0,0,112,65,0,255,127,71,0,0,128,59,0,0,128,47,73,70,131,5,75,6,158,63,77,6,158,63,80,6,158,63,30,55,190,121,255,255,127,255,255,127,127,1,0,0,0,192,255,0,0,128,255,0,0,128,127};
   Console::WriteLine( "This example of the BitConverter::ToSingle( unsigned "
   "char[ ], int ) \nmethod generates the following output. It "
   "converts elements of a \nbyte array to float values.\n" );
   WriteMultiLineByteArray( byteArray );
   Console::WriteLine( "{0,5}{1,17}{2,18:E7}", "index", "array elements", "float" );
   Console::WriteLine( "{0,5}{1,17}{2,18:E7}", "-----", "--------------", "-----" );
   
   // Convert byte array elements to float values.
   BAToSingle( byteArray, 0 );
   BAToSingle( byteArray, 2 );
   BAToSingle( byteArray, 6 );
   BAToSingle( byteArray, 10 );
   BAToSingle( byteArray, 14 );
   BAToSingle( byteArray, 18 );
   BAToSingle( byteArray, 22 );
   BAToSingle( byteArray, 26 );
   BAToSingle( byteArray, 30 );
   BAToSingle( byteArray, 34 );
   BAToSingle( byteArray, 38 );
   BAToSingle( byteArray, 42 );
   BAToSingle( byteArray, 45 );
   BAToSingle( byteArray, 49 );
   BAToSingle( byteArray, 51 );
   BAToSingle( byteArray, 55 );
   BAToSingle( byteArray, 59 );
}

/*
This example of the BitConverter::ToSingle( unsigned char[ ], int )
method generates the following output. It converts elements of a
byte array to float values.

initial unsigned char array
---------------------------
00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
80-2F-49-46-83-05-4B-06-9E-3F-4D-06-9E-3F-50-06-9E-3F-1E-37-
BE-79-FF-FF-7F-FF-FF-7F-7F-01-00-00-00-C0-FF-00-00-80-FF-00-
00-80-7F

index   array elements             float
-----   --------------             -----
    0      00-00-00-00    0.0000000E+000
    2      00-00-80-3F    1.0000000E+000
    6      00-00-70-41    1.5000000E+001
   10      00-FF-7F-47    6.5535000E+004
   14      00-00-80-3B    3.9062500E-003
   18      00-00-80-2F    2.3283064E-010
   22      49-46-83-05    1.2345000E-035
   26      4B-06-9E-3F    1.2345671E+000
   30      4D-06-9E-3F    1.2345673E+000
   34      50-06-9E-3F    1.2345676E+000
   38      1E-37-BE-79    1.2345679E+035
   42      FF-FF-7F-FF   -3.4028235E+038
   45      FF-FF-7F-7F    3.4028235E+038
   49      01-00-00-00    1.4012985E-045
   51      00-00-C0-FF               NaN
   55      00-00-80-FF         -Infinity
   59      00-00-80-7F          Infinity
*/
// Example of the BitConverter.ToSingle method.
using System;

class BytesToSingleDemo
{
    const string formatter = "{0,5}{1,17}{2,18:E7}";

    // Convert four byte array elements to a float and display it.
    public static void BAToSingle( byte[ ] bytes, int index )
    {
        float value = BitConverter.ToSingle( bytes, index );

        Console.WriteLine( formatter, index,
            BitConverter.ToString( bytes, index, 4 ), 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, 128,  63,   0,   0, 112,  65,
              0, 255, 127,  71,   0,   0, 128,  59,   0,   0,
            128,  47,  73,  70, 131,   5,  75,   6, 158,  63,
             77,   6, 158,  63,  80,   6, 158,  63,  30,  55,
            190, 121, 255, 255, 127, 255, 255, 127, 127,   1,
              0,   0,   0, 192, 255,   0,   0, 128, 255,   0,
              0, 128, 127 };

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

        WriteMultiLineByteArray( byteArray );

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

        // Convert byte array elements to float values.
        BAToSingle( byteArray, 0 );
        BAToSingle( byteArray, 2 );
        BAToSingle( byteArray, 6 );
        BAToSingle( byteArray, 10 );
        BAToSingle( byteArray, 14 );
        BAToSingle( byteArray, 18 );
        BAToSingle( byteArray, 22 );
        BAToSingle( byteArray, 26 );
        BAToSingle( byteArray, 30 );
        BAToSingle( byteArray, 34 );
        BAToSingle( byteArray, 38 );
        BAToSingle( byteArray, 42 );
        BAToSingle( byteArray, 45 );
        BAToSingle( byteArray, 49 );
        BAToSingle( byteArray, 51 );
        BAToSingle( byteArray, 55 );
        BAToSingle( byteArray, 59 );
    }
}

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

initial byte array
------------------
00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
80-2F-49-46-83-05-4B-06-9E-3F-4D-06-9E-3F-50-06-9E-3F-1E-37-
BE-79-FF-FF-7F-FF-FF-7F-7F-01-00-00-00-C0-FF-00-00-80-FF-00-
00-80-7F

index   array elements             float
-----   --------------             -----
    0      00-00-00-00    0.0000000E+000
    2      00-00-80-3F    1.0000000E+000
    6      00-00-70-41    1.5000000E+001
   10      00-FF-7F-47    6.5535000E+004
   14      00-00-80-3B    3.9062500E-003
   18      00-00-80-2F    2.3283064E-010
   22      49-46-83-05    1.2345000E-035
   26      4B-06-9E-3F    1.2345671E+000
   30      4D-06-9E-3F    1.2345673E+000
   34      50-06-9E-3F    1.2345676E+000
   38      1E-37-BE-79    1.2345679E+035
   42      FF-FF-7F-FF   -3.4028235E+038
   45      FF-FF-7F-7F    3.4028235E+038
   49      01-00-00-00    1.4012985E-045
   51      00-00-C0-FF               NaN
   55      00-00-80-FF         -Infinity
   59      00-00-80-7F          Infinity
*/
open System

let print obj1 obj2 obj3 = printfn $"{obj1,5}{obj2,17}{obj3,18:E7}"

// Convert four byte array elements to a float and display it.
let BAToSingle bytes index =
    let value = BitConverter.ToSingle(bytes, index)

    print index (BitConverter.ToString(bytes, index, 4)) 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; 128uy; 63uy; 0uy; 0uy; 112uy; 65uy
       0uy; 255uy; 127uy; 71uy; 0uy; 0uy; 128uy; 59uy; 0uy; 0uy
       128uy; 47uy; 73uy; 70uy; 131uy; 5uy; 75uy; 6uy; 158uy; 63uy
       77uy; 6uy; 158uy; 63uy; 80uy; 6uy; 158uy; 63uy; 30uy; 55uy
       190uy; 121uy; 255uy; 255uy; 127uy; 255uy; 255uy; 127uy; 127uy; 1uy
       0uy; 0uy; 0uy; 192uy; 255uy; 0uy; 0uy; 128uy; 255uy; 0uy
       0uy; 128uy; 127uy |]

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

writeMultiLineByteArray byteArray

print "index" "array elements" "float"
print "-----" "--------------" "-----"

// Convert byte array elements to float values.
BAToSingle byteArray 0 
BAToSingle byteArray 2 
BAToSingle byteArray 6 
BAToSingle byteArray 10 
BAToSingle byteArray 14 
BAToSingle byteArray 18 
BAToSingle byteArray 22 
BAToSingle byteArray 26 
BAToSingle byteArray 30 
BAToSingle byteArray 34 
BAToSingle byteArray 38 
BAToSingle byteArray 42 
BAToSingle byteArray 45 
BAToSingle byteArray 49 
BAToSingle byteArray 51 
BAToSingle byteArray 55 
BAToSingle byteArray 59 


// This example of the BitConverter.ToSingle( byte( ), int )
// method generates the following output. It converts elements
// of a byte array to float values.
//
// initial byte array
// ------------------
// 00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
// 00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
// 80-2F-49-46-83-05-4B-06-9E-3F-4D-06-9E-3F-50-06-9E-3F-1E-37-
// 00-80-7F
//
// index   array elements             float
// -----   --------------             -----
//     0      00-00-00-00    0.0000000E+000
//     2      00-00-80-3F    1.0000000E+000
//     6      00-00-70-41    1.5000000E+001
//    10      00-FF-7F-47    6.5535000E+004
//    14      00-00-80-3B    3.9062500E-003
//    18      00-00-80-2F    2.3283064E-010
//    22      49-46-83-05    1.2345000E-035
//    26      4B-06-9E-3F    1.2345671E+000
//    30      4D-06-9E-3F    1.2345673E+000
//    34      50-06-9E-3F    1.2345676E+000
//    38      1E-37-BE-79    1.2345679E+035
//    42      FF-FF-7F-FF   -3.4028235E+038
//    45      FF-FF-7F-7F    3.4028235E+038
//    49      01-00-00-00    1.4012985E-045
//    51      00-00-C0-FF               NaN
//    55      00-00-80-FF                -∞
//    59      00-00-80-7F                 ∞
' Example of the BitConverter.ToSingle method.
Module BytesToSingleDemo

    Const formatter As String = "{0,5}{1,17}{2,18:E7}"
 
    ' Convert four Byte array elements to a Single and display it.
    Sub BAToSingle( bytes( ) As Byte, index As Integer )

        Dim value As Single = BitConverter.ToSingle( bytes, index )

        Console.WriteLine( formatter, index, _
            BitConverter.ToString( bytes, index, 4 ), 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, 128,  63,   0,   0, 112,  65, _
              0, 255, 127,  71,   0,   0, 128,  59,   0,   0, _
            128,  47,  73,  70, 131,   5,  75,   6, 158,  63, _
             77,   6, 158,  63,  80,   6, 158,  63,  30,  55, _
            190, 121, 255, 255, 127, 255, 255, 127, 127,   1, _
              0,   0,   0, 192, 255,   0,   0, 128, 255,   0, _
              0, 128, 127 }

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

        WriteMultiLineByteArray( byteArray )

        Console.WriteLine( formatter, "index", "array elements", _
            "Single" )
        Console.WriteLine( formatter, "-----", "--------------", _
            "------" )
          
        ' Convert Byte array elements to Single values.
        BAToSingle( byteArray, 0 )
        BAToSingle( byteArray, 2 )
        BAToSingle( byteArray, 6 )
        BAToSingle( byteArray, 10 )
        BAToSingle( byteArray, 14 )
        BAToSingle( byteArray, 18 )
        BAToSingle( byteArray, 22 )
        BAToSingle( byteArray, 26 )
        BAToSingle( byteArray, 30 )
        BAToSingle( byteArray, 34 )
        BAToSingle( byteArray, 38 )
        BAToSingle( byteArray, 42 )
        BAToSingle( byteArray, 45 )
        BAToSingle( byteArray, 49 )
        BAToSingle( byteArray, 51 )
        BAToSingle( byteArray, 55 )
        BAToSingle( byteArray, 59 )
    End Sub 
End Module

' This example of the BitConverter.ToSingle( Byte( ), Integer )
' method generates the following output. It converts elements
' of a Byte array to Single values.
' 
' initial Byte array
' ------------------
' 00-00-00-00-80-3F-00-00-70-41-00-FF-7F-47-00-00-80-3B-00-00-
' 80-2F-49-46-83-05-4B-06-9E-3F-4D-06-9E-3F-50-06-9E-3F-1E-37-
' BE-79-FF-FF-7F-FF-FF-7F-7F-01-00-00-00-C0-FF-00-00-80-FF-00-
' 00-80-7F
' 
' index   array elements            Single
' -----   --------------            ------
'     0      00-00-00-00    0.0000000E+000
'     2      00-00-80-3F    1.0000000E+000
'     6      00-00-70-41    1.5000000E+001
'    10      00-FF-7F-47    6.5535000E+004
'    14      00-00-80-3B    3.9062500E-003
'    18      00-00-80-2F    2.3283064E-010
'    22      49-46-83-05    1.2345000E-035
'    26      4B-06-9E-3F    1.2345671E+000
'    30      4D-06-9E-3F    1.2345673E+000
'    34      50-06-9E-3F    1.2345676E+000
'    38      1E-37-BE-79    1.2345679E+035
'    42      FF-FF-7F-FF   -3.4028235E+038
'    45      FF-FF-7F-7F    3.4028235E+038
'    49      01-00-00-00    1.4012985E-045
'    51      00-00-C0-FF               NaN
'    55      00-00-80-FF         -Infinity
'    59      00-00-80-7F          Infinity

備註

方法 ToSingle 會將位元組從索引 startIndex 轉換成 startIndex + 3 轉換為 Single 值。 陣列中的位元組順序必須反映電腦系統架構的結束度。 如需詳細資訊,請參閱 的 BitConverter 一節。

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適用於