Converts a specified value to a double-precision floating point number.
Overload List
Converts the value of the specified Boolean value to the equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Boolean) As Double
[C#] public static double ToDouble(bool);
[C++] public: static double ToDouble(bool);
[JScript] public static function ToDouble(Boolean) : double;
Converts the value of the specified 8-bit unsigned integer to the equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Byte) As Double
[C#] public static double ToDouble(byte);
[C++] public: static double ToDouble(unsigned char);
[JScript] public static function ToDouble(Byte) : double;
Calling this method always throws InvalidCastException.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Char) As Double
[C#] public static double ToDouble(char);
[C++] public: static double ToDouble(__wchar_t);
[JScript] public static function ToDouble(Char) : double;
Calling this method always throws InvalidCastException.
[Visual Basic] Overloads Public Shared Function ToDouble(DateTime) As Double
[C#] public static double ToDouble(DateTime);
[C++] public: static double ToDouble(DateTime);
[JScript] public static function ToDouble(DateTime) : double;
Converts the value of the specified Decimal number to an equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Decimal) As Double
[C#] public static double ToDouble(decimal);
[C++] public: static double ToDouble(Decimal);
[JScript] public static function ToDouble(Decimal) : double;
Returns the specified double-precision floating point number; no actual conversion is performed.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Double) As Double
[C#] public static double ToDouble(double);
[C++] public: static double ToDouble(double);
[JScript] public static function ToDouble(double) : double;
Converts the value of the specified 16-bit signed integer to an equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Short) As Double
[C#] public static double ToDouble(short);
[C++] public: static double ToDouble(short);
[JScript] public static function ToDouble(Int16) : double;
Converts the value of the specified 32-bit signed integer to an equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Integer) As Double
[C#] public static double ToDouble(int);
[C++] public: static double ToDouble(int);
[JScript] public static function ToDouble(int) : double;
Converts the value of the specified 64-bit signed integer to an equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Long) As Double
[C#] public static double ToDouble(long);
[C++] public: static double ToDouble(__int64);
[JScript] public static function ToDouble(long) : double;
Converts the value of the specified Object to a double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Object) As Double
[C#] public static double ToDouble(object);
[C++] public: static double ToDouble(Object*);
[JScript] public static function ToDouble(Object) : double;
Converts the value of the specified 8-bit signed integer to the equivalent double-precision floating point number. This method is not CLS-compliant.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(SByte) As Double
[C#] public static double ToDouble(sbyte);
[C++] public: static double ToDouble(char);
[JScript] public static function ToDouble(SByte) : double;
Converts the value of the specified single-precision floating point number to an equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(Single) As Double
[C#] public static double ToDouble(float);
[C++] public: static double ToDouble(float);
[JScript] public static function ToDouble(float) : double;
Converts the specified String representation of a number to an equivalent double-precision floating point number.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(String) As Double
[C#] public static double ToDouble(string);
[C++] public: static double ToDouble(String*);
[JScript] public static function ToDouble(String) : double;
Converts the value of the specified 16-bit unsigned integer to the equivalent double-precision floating point number. This method is not CLS-compliant.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(UInt16) As Double
[C#] public static double ToDouble(ushort);
[C++] public: static double ToDouble(unsigned short);
[JScript] public static function ToDouble(UInt16) : double;
Converts the value of the specified 32-bit unsigned integer to an equivalent double-precision floating point number. This method is not CLS-compliant.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(UInt32) As Double
[C#] public static double ToDouble(uint);
[C++] public: static double ToDouble(unsigned int);
[JScript] public static function ToDouble(UInt32) : double;
Converts the value of the specified 64-bit unsigned integer to an equivalent double-precision floating point number. This method is not CLS-compliant.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(UInt64) As Double
[C#] public static double ToDouble(ulong);
[C++] public: static double ToDouble(unsigned __int64);
[JScript] public static function ToDouble(UInt64) : double;
Converts the value of the specified Object to an double-precision floating point number using the specified culture-specific formatting information.
[Visual Basic] Overloads Public Shared Function ToDouble(Object, IFormatProvider) As Double
[C#] public static double ToDouble(object, IFormatProvider);
[C++] public: static double ToDouble(Object*, IFormatProvider*);
[JScript] public static function ToDouble(Object, IFormatProvider) : double;
Converts the specified String representation of a number to an equivalent double-precision floating point number using the specified culture-specific formatting information.
Supported by the .NET Compact Framework.
[Visual Basic] Overloads Public Shared Function ToDouble(String, IFormatProvider) As Double
[C#] public static double ToDouble(string, IFormatProvider);
[C++] public: static double ToDouble(String*, IFormatProvider*);
[JScript] public static function ToDouble(String, IFormatProvider) : double;
Example
[Visual Basic, C#, C++] The following code example converts String representations of Double values with the ToDouble method, using an IFormatProvider object.
[Visual Basic, C#, C++] Note This example shows how to use one of the overloaded versions of ToDouble. For other examples that might be available, see the individual overload topics.
[Visual Basic]
' Example of the Convert.ToDouble( String ) and
' Convert.ToDouble( String, IFormatProvider ) methods.
Imports System
Imports System.Globalization
Imports Microsoft.VisualBasic
Module ToDoubleProviderDemo
Dim formatter As String = "{0,-22}{1,-20}{2}"
' Get the exception type name; remove the namespace prefix.
Function GetExceptionType( ex As Exception ) As String
Dim exceptionType As String = ex.GetType( ).ToString( )
GetExceptionType = exceptionType.Substring( _
exceptionType.LastIndexOf( "."c ) + 1 )
End Function
Sub ConvertToDouble( numericStr As String, _
provider As IFormatProvider )
Dim defaultValue As Object
Dim providerValue As Object
' Convert numericStr to Double without a format provider.
Try
defaultValue = Convert.ToDouble( numericStr )
Catch ex As Exception
defaultValue = GetExceptionType( ex )
End Try
' Convert numericStr to Double with a format provider.
Try
providerValue = Convert.ToDouble( numericStr, provider )
Catch ex As Exception
providerValue = GetExceptionType( ex )
End Try
Console.WriteLine( formatter, numericStr, _
defaultValue, providerValue )
End Sub
Sub Main( )
' Create a NumberFormatInfo object and set several of its
' properties that apply to numbers.
Dim provider As NumberFormatInfo = new NumberFormatInfo( )
provider.NumberDecimalSeparator = ","
provider.NumberGroupSeparator = "."
provider.NumberGroupSizes = New Integer( ) { 3 }
Console.WriteLine( "This example of" & vbCrLf & _
" Convert.ToDouble( String ) and " & vbCrLf & _
" Convert.ToDouble( String, IFormatProvider ) " & _
vbCrLf & "generates the " & _
"following output when run in the [{0}] culture.", _
CultureInfo.CurrentCulture.Name )
Console.WriteLine( vbCrLf & _
"Several strings are converted to Double values, " & _
"using " & vbCrLf & "default formatting " & _
"and a NumberFormatInfo object." & vbCrLf )
Console.WriteLine( formatter, "String to convert", _
"Default/exception", "Provider/exception" )
Console.WriteLine( formatter, "-----------------", _
"-----------------", "------------------" )
' Convert strings, with and without an IFormatProvider.
ConvertToDouble( "123456789", provider )
ConvertToDouble( "12345.6789", provider )
ConvertToDouble( "12345,6789", provider )
ConvertToDouble( "123,456.789", provider )
ConvertToDouble( "123.456,789", provider )
ConvertToDouble( "123,456,789.0123", provider )
ConvertToDouble( "123.456.789,0123", provider )
End Sub
End Module
' This example of
' Convert.ToDouble( String ) and
' Convert.ToDouble( String, IFormatProvider )
' generates the following output when run in the [en-US] culture.
'
' Several strings are converted to Double values, using
' default formatting and a NumberFormatInfo object.
'
' String to convert Default/exception Provider/exception
' ----------------- ----------------- ------------------
' 123456789 123456789 123456789
' 12345.6789 12345.6789 123456789
' 12345,6789 123456789 12345.6789
' 123,456.789 123456.789 FormatException
' 123.456,789 FormatException 123456.789
' 123,456,789.0123 123456789.0123 FormatException
' 123.456.789,0123 FormatException 123456789.0123
[C#]
// Example of the Convert.ToDouble( String ) and
// Convert.ToDouble( String, IFormatProvider ) methods.
using System;
using System.Globalization;
class ToDoubleProviderDemo
{
static string formatter = "{0,-22}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
static string GetExceptionType( Exception ex )
{
string exceptionType = ex.GetType( ).ToString( );
return exceptionType.Substring(
exceptionType.LastIndexOf( '.' ) + 1 );
}
static void ConvertToDouble( string numericStr,
IFormatProvider provider )
{
object defaultValue;
object providerValue;
// Convert numericStr to double without a format provider.
try
{
defaultValue = Convert.ToDouble( numericStr );
}
catch( Exception ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to double with a format provider.
try
{
providerValue = Convert.ToDouble( numericStr, provider );
}
catch( Exception ex )
{
providerValue = GetExceptionType( ex );
}
Console.WriteLine( formatter, numericStr, defaultValue,
providerValue );
}
static void Main( )
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo provider = new NumberFormatInfo( );
provider.NumberDecimalSeparator = ",";
provider.NumberGroupSeparator = ".";
provider.NumberGroupSizes = new int[ ] { 3 };
Console.WriteLine(
"This example of\n Convert.ToDouble( String ) and \n" +
" Convert.ToDouble( String, IFormatProvider ) \n" +
"generates the following output when run in the " +
"[{0}] culture.",
CultureInfo.CurrentCulture.Name );
Console.WriteLine( "\nSeveral " +
"strings are converted to double values, using \n" +
"default formatting and a NumberFormatInfo object.\n");
Console.WriteLine( formatter, "String to convert",
"Default/exception", "Provider/exception" );
Console.WriteLine( formatter, "-----------------",
"-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToDouble( "123456789", provider );
ConvertToDouble( "12345.6789", provider );
ConvertToDouble( "12345,6789", provider );
ConvertToDouble( "123,456.789", provider );
ConvertToDouble( "123.456,789", provider );
ConvertToDouble( "123,456,789.0123", provider );
ConvertToDouble( "123.456.789,0123", provider );
}
}
/*
This example of
Convert.ToDouble( String ) and
Convert.ToDouble( String, IFormatProvider )
generates the following output when run in the [en-US] culture.
Several strings are converted to double values, using
default formatting and a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
123456789 123456789 123456789
12345.6789 12345.6789 123456789
12345,6789 123456789 12345.6789
123,456.789 123456.789 FormatException
123.456,789 FormatException 123456.789
123,456,789.0123 123456789.0123 FormatException
123.456.789,0123 FormatException 123456789.0123
*/
[C++]
// Example of the Convert::ToDouble( String ) and
// Convert::ToDouble( String, IFormatProvider ) methods.
#using <mscorlib.dll>
using namespace System;
using namespace System::Globalization;
const __wchar_t* formatter = L"{0,-22}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
String* GetExceptionType( Exception* ex )
{
String* exceptionType = ex->GetType( )->ToString( );
return exceptionType->Substring(
exceptionType->LastIndexOf( '.' ) + 1 );
}
void ConvertToDouble( String* numericStr,
IFormatProvider* provider )
{
Object* defaultValue;
Object* providerValue;
// Convert numericStr to Double without a format provider.
try
{
defaultValue = __box( Convert::ToDouble( numericStr ) );
}
catch( Exception* ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Double with a format provider.
try
{
providerValue = __box(
Convert::ToDouble( numericStr, provider ) );
}
catch( Exception* ex )
{
providerValue = GetExceptionType( ex );
}
Console::WriteLine( new String( formatter ), numericStr,
defaultValue, providerValue );
}
void main( )
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo* provider = new NumberFormatInfo( );
provider->NumberDecimalSeparator = S",";
provider->NumberGroupSeparator = S".";
Int32 sizes __gc [] = { 3 };
provider->NumberGroupSizes = sizes;
Console::WriteLine(
S"This example of\n Convert::ToDouble( String* ) and \n"
S" Convert::ToDouble( String*, IFormatProvider* ) \n"
S"generates the following output when run in the "
S"[{0}] culture.",
CultureInfo::CurrentCulture->Name );
Console::WriteLine( S"\nSeveral "
S"strings are converted to Double values, using \n"
S"default formatting and a NumberFormatInfo object.\n");
Console::WriteLine( new String( formatter ), S"String to convert",
S"Default/exception", S"Provider/exception" );
Console::WriteLine( new String( formatter ), S"-----------------",
S"-----------------", S"------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToDouble( S"123456789", provider );
ConvertToDouble( S"12345.6789", provider );
ConvertToDouble( S"12345,6789", provider );
ConvertToDouble( S"123,456.789", provider );
ConvertToDouble( S"123.456,789", provider );
ConvertToDouble( S"123,456,789.0123", provider );
ConvertToDouble( S"123.456.789,0123", provider );
}
/*
This example of
Convert::ToDouble( String* ) and
Convert::ToDouble( String*, IFormatProvider* )
generates the following output when run in the [en-US] culture.
Several strings are converted to Double values, using
default formatting and a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
123456789 123456789 123456789
12345.6789 12345.6789 123456789
12345,6789 123456789 12345.6789
123,456.789 123456.789 FormatException
123.456,789 FormatException 123456.789
123,456,789.0123 123456789.0123 FormatException
123.456.789,0123 FormatException 123456789.0123
*/
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button .gif)
in the upper-left corner of the page.
See Also
Convert Class | Convert Members | System Namespace