BitConverter.ToDouble Method
Microsoft Silverlight will reach end of support after October 2021. Learn more.
Returns a double-precision floating point number converted from eight bytes at a specified position in a byte array.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
<SecuritySafeCriticalAttribute> _
Public Shared Function ToDouble ( _
value As Byte(), _
startIndex As Integer _
) As Double
[SecuritySafeCriticalAttribute]
public static double ToDouble(
byte[] value,
int startIndex
)
Parameters
- value
Type: array<System.Byte[]
An array of bytes.
- startIndex
Type: System.Int32
The starting position within value.
Return Value
Type: System.Double
A double precision floating point number formed by eight bytes beginning at startIndex.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentException | startIndex is greater than or equal to the length of value minus 7, and is less than or equal to the length of value minus 1. |
| ArgumentNullException | value is nulla null reference (Nothing in Visual Basic). |
| ArgumentOutOfRangeException | startIndex is less than zero or greater than the length of value minus 1. |
Examples
The following code example converts elements of Byte arrays to Double values with the ToDouble method.
' Example of the BitConverter.ToDouble method.
Module Example
Const formatter As String = "{0,5}{1,27}{2,27:E16}"
' Convert eight Byte array elements to a Double and display it.
Sub BAToDouble(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal bytes() As Byte, ByVal index As Integer)
Dim value As Double = BitConverter.ToDouble(bytes, index)
outputBlock.Text &= String.Format(formatter, index, _
BitConverter.ToString(bytes, index, 8), value) & vbCrLf
End Sub
' Display a Byte array, using multiple lines if necessary.
Sub WriteMultiLineByteArray(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal bytes() As Byte)
Const rowSize As Integer = 20
Dim iter As Integer
outputBlock.Text &= "initial Byte array" & vbCrLf
outputBlock.Text &= "------------------" & vbCrLf
For iter = 0 To bytes.Length - rowSize - 1 Step rowSize
outputBlock.Text &= String.Format( _
BitConverter.ToString(bytes, iter, rowSize))
outputBlock.Text &= "-" & vbCrLf
Next iter
outputBlock.Text &= String.Format(BitConverter.ToString(bytes, iter)) & vbCrLf
outputBlock.Text &= vbCrLf
End Sub
Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
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}
outputBlock.Text &= String.Format( _
"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) & vbCrLf
WriteMultiLineByteArray(outputBlock, byteArray)
outputBlock.Text &= String.Format(formatter, "index", "array elements", _
"Double") & vbCrLf
outputBlock.Text &= String.Format(formatter, "-----", "--------------", _
"------") & vbCrLf
' Convert Byte array elements to Double values.
BAToDouble(outputBlock, byteArray, 0)
BAToDouble(outputBlock, byteArray, 2)
BAToDouble(outputBlock, byteArray, 10)
BAToDouble(outputBlock, byteArray, 18)
BAToDouble(outputBlock, byteArray, 26)
BAToDouble(outputBlock, byteArray, 34)
BAToDouble(outputBlock, byteArray, 42)
BAToDouble(outputBlock, byteArray, 50)
BAToDouble(outputBlock, byteArray, 58)
BAToDouble(outputBlock, byteArray, 66)
BAToDouble(outputBlock, byteArray, 74)
BAToDouble(outputBlock, byteArray, 82)
BAToDouble(outputBlock, byteArray, 89)
BAToDouble(outputBlock, byteArray, 97)
BAToDouble(outputBlock, byteArray, 99)
BAToDouble(outputBlock, byteArray, 107)
BAToDouble(outputBlock, 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
// Example of the BitConverter.ToDouble method.
using System;
class Example
{
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(System.Windows.Controls.TextBlock outputBlock, byte[] bytes, int index)
{
double value = BitConverter.ToDouble(bytes, index);
outputBlock.Text += String.Format(formatter, index,
BitConverter.ToString(bytes, index, 8), value) + "\n";
}
// Display a byte array, using multiple lines if necessary.
public static void WriteMultiLineByteArray(System.Windows.Controls.TextBlock outputBlock, byte[] bytes)
{
const int rowSize = 20;
int iter;
outputBlock.Text += "initial byte array" + "\n";
outputBlock.Text += "------------------" + "\n";
for (iter = 0; iter < bytes.Length - rowSize; iter += rowSize)
{
outputBlock.Text += String.Format(
BitConverter.ToString(bytes, iter, rowSize));
outputBlock.Text += "-" + "\n";
}
outputBlock.Text += String.Format(BitConverter.ToString(bytes, iter)) + "\n";
outputBlock.Text += "\n";
}
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
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 };
outputBlock.Text += String.Format(
"This example of the BitConverter.ToDouble( byte[ ], " +
"int ) \nmethod generates the following output. It " +
"converts elements \nof a byte array to double values.\n") + "\n";
WriteMultiLineByteArray(outputBlock, byteArray);
outputBlock.Text += String.Format(formatter, "index", "array elements",
"double") + "\n";
outputBlock.Text += String.Format(formatter, "-----", "--------------",
"------") + "\n";
// Convert byte array elements to double values.
BAToDouble(outputBlock, byteArray, 0);
BAToDouble(outputBlock, byteArray, 2);
BAToDouble(outputBlock, byteArray, 10);
BAToDouble(outputBlock, byteArray, 18);
BAToDouble(outputBlock, byteArray, 26);
BAToDouble(outputBlock, byteArray, 34);
BAToDouble(outputBlock, byteArray, 42);
BAToDouble(outputBlock, byteArray, 50);
BAToDouble(outputBlock, byteArray, 58);
BAToDouble(outputBlock, byteArray, 66);
BAToDouble(outputBlock, byteArray, 74);
BAToDouble(outputBlock, byteArray, 82);
BAToDouble(outputBlock, byteArray, 89);
BAToDouble(outputBlock, byteArray, 97);
BAToDouble(outputBlock, byteArray, 99);
BAToDouble(outputBlock, byteArray, 107);
BAToDouble(outputBlock, 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
*/
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
XNA Framework
Supported in: Xbox 360, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.