Articolo
11/18/2011

TypeConverter Class

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

Provides a unified way of converting types of values to other types. TypeConverter typically supports string-to-object conversion, either for property editors in design environments, or to enable XAML usages.

Inheritance Hierarchy

System.Object
  System.ComponentModel.TypeConverter
    System.UriTypeConverter
    System.Windows.Controls.DataGridLengthConverter
    System.Windows.Controls.DateTimeTypeConverter
    System.Windows.DurationConverter
    System.Windows.Media.ImageSourceConverter
    System.Windows.NullableBoolConverter
    System.Windows.PropertyPathConverter

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

Syntax

'Declaration
Public Class TypeConverter

public class TypeConverter

The TypeConverter type exposes the following members.

Constructors

	Name	Description
	TypeConverter	Initializes a new instance of the TypeConverter class.

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Methods

	Name	Description
	CanConvertFrom(Type)	Returns whether the type converter can convert an object from the specified type to the type of this converter.
	CanConvertFrom(ITypeDescriptorContext, Type)	Returns whether the type converter can convert an object from the specified type to the type of this converter.
	CanConvertTo(Type)	Returns whether the type converter can convert an object to the specified type.
	CanConvertTo(ITypeDescriptorContext, Type)	Returns whether the type converter can convert an object to the specified type.
	ConvertFrom(Object)	Converts from the specified value to the type of this converter.
	ConvertFrom(ITypeDescriptorContext, CultureInfo, Object)	Converts from the specified value to the intended conversion type of the converter.
	ConvertFromString	Converts the specified text to an object.
	ConvertTo(Object, Type)	Converts the specified value object to the specified type.
	ConvertTo(ITypeDescriptorContext, CultureInfo, Object, Type)	Converts the specified value object to the specified type.
	ConvertToString	Converts the specified object to a string representation.
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Remarks

The most common type of converter is one that converts to and from a text or string representation. The type converter for a class is associated with the class by applying a TypeConverterAttribute in the class definition. Unless this attribute is overridden, all classes that inherit from this class use the same type converter as the base class.

The most common scenario for TypeConverter in Silverlight is to support setting XAML attribute values and generating object values when XAML is parsed, both for Silverlight defined classes and custom classes. See TypeConverters and XAML.

Notes to Implementers

To support the string creation syntax of custom types that are specified as attributes in XAML, you should implement CanConvertFrom(ITypeDescriptorContext, Type) and ConvertFrom(ITypeDescriptorContext, CultureInfo, Object) in your TypeConverter class.

For Silverlight 4, implementing CanConvertTo and ConvertTo is not crucial, because Silverlight 4 XAML does not support a general serialization mechanism. However, you might still consider providing a basic CanConvertTo and ConvertTo implementation that reverses the ConvertFrom(ITypeDescriptorContext, CultureInfo, Object) in your TypeConverter conversion. This will produce a more robust and generalized TypeConverter for anyone that specifically calls the ConvertTo method.

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.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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