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OpacityConverter.ConvertFrom Method

Definition

Converts the specified object to the converter's native type.

public:
 override System::Object ^ ConvertFrom(System::ComponentModel::ITypeDescriptorContext ^ context, System::Globalization::CultureInfo ^ culture, System::Object ^ value);
public override object ConvertFrom (System.ComponentModel.ITypeDescriptorContext context, System.Globalization.CultureInfo culture, object value);
public override object? ConvertFrom (System.ComponentModel.ITypeDescriptorContext? context, System.Globalization.CultureInfo? culture, object value);
override this.ConvertFrom : System.ComponentModel.ITypeDescriptorContext * System.Globalization.CultureInfo * obj -> obj
Public Overrides Function ConvertFrom (context As ITypeDescriptorContext, culture As CultureInfo, value As Object) As Object

Parameters

context
ITypeDescriptorContext

A ITypeDescriptorContext that provides information about the context of a type converter.

culture
CultureInfo

The locale information for the conversion.

value
Object

The object to convert.

Returns

An Object that represents the converted value.

Exceptions

The object was not a supported type for the conversion.

value could not be properly converted to type Double.

-or-

The resulting converted value was less than zero percent or greater than one hundred percent.

Remarks

The ConvertFrom method is specialized to convert String values that represent percentages or decimal fractions to their corresponding Double values, which represent the opacity as a percentage. Types other than String are passed to the base class implementation of this method.

Notes to Inheritors

Override this method to provide your own conversion requirements.

You can use the context parameter to extract additional information about the environment this converter is being invoked from. The parameter may be null, so you should always verify the contents. Also, properties on the ITypeDescriptorContext may also return null.

Applies to

See also