# Convert.ToBoolean Method (Double)

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

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

## Syntax

``````'Declaration
Public Shared Function ToBoolean ( _
value As Double _
) As Boolean
``````
``````public static bool ToBoolean(
double value
)
``````

#### Parameters

• value
Type: System.Double
A double-precision floating point number.

#### Return Value

Type: System.Boolean
true if value is not zero; otherwise, false.

## Examples

The following code sample illustrates the use of the ToBoolean method, taking a Double as a parameter.

``````Public Sub ConvertDoubleBool(ByVal doubleVal As Double)
Dim boolVal As Boolean

'Double to Boolean conversion cannot overflow.
boolVal = System.Convert.ToBoolean(doubleVal)
outputBlock.Text &= String.Format("{0} as a Boolean is: {1}.", _
doubleVal, boolVal) & vbCrLf

'Boolean to Double conversion cannot overflow.
doubleVal = System.Convert.ToDouble(boolVal)
outputBlock.Text &= String.Format("{0} as a Double is: {1}.", _
boolVal, doubleVal) & vbCrLf
End Sub
``````
``````public void ConvertDoubleBool(double doubleVal)
{
bool boolVal;
// Double to bool conversion cannot overflow.
boolVal = System.Convert.ToBoolean(doubleVal);
outputBlock.Text += String.Format("{0} as a Boolean is: {1}.",
doubleVal, boolVal) + "\n";

// bool to double conversion cannot overflow.
doubleVal = System.Convert.ToDouble(boolVal);
outputBlock.Text += String.Format("{0} as a double is: {1}.",
boolVal, doubleVal) + "\n";
}
``````

## 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.