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# Convert.ToDouble Method (Boolean)

.NET Framework 1.1

Converts the value of the specified Boolean value to the equivalent double-precision floating point number.

```[Visual Basic]
Overloads Public Shared Function ToDouble( _
ByVal value As Boolean _
) As Double
[C#]
public static double ToDouble(
bool value
);
[C++]
public: static double ToDouble(
bool value
);
[JScript]
public static function ToDouble(
value : Boolean
) : double;```

value
A Boolean value.

#### Return Value

The number 1 if value is true; otherwise, 0.

#### Example

[Visual Basic, C#, C++] The following code sample illustrates the conversion of a Boolean value to a Double one, using ToDouble.

```[Visual Basic]
Public Sub ConvertDoubleBool(ByVal doubleVal As Double)
Dim boolVal As Boolean

'Double to Boolean conversion cannot overflow.
boolVal = System.Convert.ToBoolean(doubleVal)
System.Console.WriteLine("{0} as a Boolean is: {1}.", _
doubleVal, boolVal)

'Boolean to Double conversion cannot overflow.
doubleVal = System.Convert.ToDouble(boolVal)
System.Console.WriteLine("{0} as a Double is: {1}.", _
boolVal, doubleVal)
End Sub

[C#]
public void ConvertDoubleBool(double doubleVal) {
bool    boolVal;
// Double to bool conversion cannot overflow.
boolVal = System.Convert.ToBoolean(doubleVal);
System.Console.WriteLine("{0} as a Boolean is: {1}.",
doubleVal, boolVal);

// bool to double conversion cannot overflow.
doubleVal = System.Convert.ToDouble(boolVal);
System.Console.WriteLine("{0} as a double is: {1}.",
boolVal, doubleVal);
}

[C++]

public __gc class ConvertSnippet
{
public:
void ConvertDoubleBool(double doubleVal)
{
bool boolVal;
// Double to bool conversion cannot overflow.
boolVal = System::Convert::ToBoolean(doubleVal);
System::Console::WriteLine(S" {0} as a Boolean is: {1}.",
__box(doubleVal), __box(boolVal));

// bool to double conversion cannot overflow.
doubleVal = System::Convert::ToDouble(boolVal);
System::Console::WriteLine(S" {0} as a double is: {1}.",
__box(boolVal), __box(doubleVal));
}
```

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button in the upper-left corner of the page.

#### Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework, Common Language Infrastructure (CLI) Standard