Convert.ToBoolean Method (String)
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Converts the specified String representation of a logical value to its Boolean equivalent.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- value
- Type: System.String
A String that contains the value of either TrueString or FalseString.
Return Value
Type: System.Booleantrue if value equals TrueString, or false if value equals FalseString or Nothing.
| Exception | Condition |
|---|---|
| FormatException | value is not equal to TrueString or FalseString. |
For a successful conversion to occur, the value parameter must equal either Boolean.TrueString, a string constant whose value is True, Boolean.FalseString, a string constant whose value is False, or it must be Nothing. In comparing value with Boolean.TrueString and Boolean.FalseString, the method ignores case as well as leading and trailing white space.
If you prefer not to handle an exception if the conversion fails, you can call the Boolean.TryParse method instead. It returns a Boolean value that indicates whether the conversion succeeded or failed.
The following example uses the Convert.ToBoolean(String) method to convert various strings to Boolean values.
Module Example Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock) ConvertToBoolean(outputBlock, Nothing) ConvertToBoolean(outputBlock, String.Empty) ConvertToBoolean(outputBlock, "true") ConvertToBoolean(outputBlock, "TrueString") ConvertToBoolean(outputBlock, "False") ConvertToBoolean(outputBlock, " false ") ConvertToBoolean(outputBlock, "-1") ConvertToBoolean(outputBlock, "0") End Sub Private Sub ConvertToBoolean(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal value As String) Try outputBlock.Text += String.Format("Converted '{0}' to {1}.", value, _ Convert.ToBoolean(value)) & vbCrLf Catch e As FormatException outputBlock.Text += String.Format("Unable to convert '{0}' to a Boolean.", value) & vbCrLf End Try End Sub End Module ' The example displays the following output: ' Converted '' to False. ' Unable to convert '' to a Boolean. ' Converted 'true' to True. ' Unable to convert 'TrueString' to a Boolean. ' Converted 'False' to False. ' Converted ' false ' to False. ' Unable to convert '-1' to a Boolean. ' Unable to convert '0' to a Boolean.