BitConverter.ToSingle Méthode
Définition
Important
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Surcharges
| ToSingle(ReadOnlySpan<Byte>) |
Convertit une étendue d’octets en lecture seule en une valeur à virgule flottante simple précision. |
| ToSingle(Byte[], Int32) |
Retourne un nombre à virgule flottante simple précision converti à partir de quatre octets à une position spécifiée dans un tableau d'octets. |
ToSingle(ReadOnlySpan<Byte>)
Convertit une étendue d’octets en lecture seule en une valeur à virgule flottante simple précision.
public:
static float ToSingle(ReadOnlySpan<System::Byte> value);public static float ToSingle (ReadOnlySpan<byte> value);static member ToSingle : ReadOnlySpan<byte> -> singlePublic Shared Function ToSingle (value As ReadOnlySpan(Of Byte)) As SingleParamètres
- value
- ReadOnlySpan<Byte>
Étendue en lecture seule contenant les octets à convertir.
Retours
Valeur à virgule flottante simple précision représentant les octets convertis.
Exceptions
La longueur de value est inférieure à la longueur d’une valeur Single.
S’applique à
ToSingle(Byte[], Int32)
Retourne un nombre à virgule flottante simple précision converti à partir de quatre octets à une position spécifiée dans un tableau d'octets.
public:
static float ToSingle(cli::array <System::Byte> ^ value, int startIndex);public static float ToSingle (byte[] value, int startIndex);static member ToSingle : byte[] * int -> singlePublic Shared Function ToSingle (value As Byte(), startIndex As Integer) As SingleParamètres
- value
- Byte[]
Tableau d'octets.
- startIndex
- Int32
Position de départ dans value.
Retours
Nombre à virgule flottante simple précision composé de quatre octets, à partir de startIndex.
Exceptions
startIndex est supérieur ou égal à la longueur de value moins 3, et inférieur ou égal à la longueur de value moins 1.
value a la valeur null.
startIndex est inférieur à zéro ou supérieur à la longueur de value moins 1.
Exemples
L’exemple de code suivant convertit les éléments de Byte tableaux en Single valeurs avec la ToSingle méthode.
// 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
Remarques
La ToSingle méthode convertit les octets d’index startIndex en startIndex + 3 en valeur Single . L’ordre des octets dans le tableau doit refléter l’endianité de l’architecture du système informatique. Pour plus d’informations, consultez la section Notes de BitConverter.