项目
11/18/2011

NullableBoolConverter.ConvertFrom Method (ITypeDescriptorContext, CultureInfo, Object)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Converts the specified object to a Nullable<T> type (using the Boolean type constraint on the generic).

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

Syntax

'Declaration
Public Overrides Function ConvertFrom ( _
    context As ITypeDescriptorContext, _
    culture As CultureInfo, _
    value As Object _
) As Object

public override Object ConvertFrom(
    ITypeDescriptorContext context,
    CultureInfo culture,
    Object value
)

Parameters

context
Type: System.ComponentModel.ITypeDescriptorContext
An ITypeDescriptorContext that provides a format context.

culture
Type: System.Globalization.CultureInfo
The CultureInfo to use as the current culture.

value
Type: System.Object
The object to convert to a Nullable<T> type (using the Boolean type constraint on the generic).

Return Value

Type: System.Object
A Nullable<T> type (using the Boolean type constraint on the generic) that represents the converted object.

Exceptions

Exception	Condition
NotSupportedException	The conversion attempt failed. value is not a String, Boolean, or Nullable<T> (using the Boolean type constraint on the generic) type.

Remarks

The NullableBoolConverter performs conversions between strings and Boolean types or Nullable<T> types (using the Boolean type constraint on the generic). Any other conversion attempts will cause an exception.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, 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.

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