Convert.ToBoolean Method (String)

 

Converts the specified string representation of a logical value to its Boolean equivalent.

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

Public Shared Function ToBoolean (
	value As String
) As Boolean

Parameters

value
Type: System.String

A string that contains the value of either Boolean.TrueString or Boolean.FalseString.

Return Value

Type: System.Boolean

true if value equals TrueString, or false if value equals FalseString or null.

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 constant whose value is True, Boolean.FalseString, a constant whose value is False, or it must be null. 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 BooleanConversion
   Public Sub Main()
      Dim values() As String = { Nothing, String.Empty, "true", 
                                 "TrueString", "False", "    false    ",
                                 "-1", "0" }
      For Each value In values                                 
         Try
            Console.WriteLine("Converted '{0}' to {1}.", value, _ 
                              Convert.ToBoolean(value))
         Catch e As FormatException
            Console.WriteLine("Unable to convert '{0}' to a Boolean.", value)
         End Try
      Next
   End Sub
End Module
' The example displays the following output to the console:
'       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.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Return to top
Show: