LengthConverter Class

Reference

Definition

Namespace:: System.Windows

Assembly:: PresentationFramework.dll

Important

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Converts instances of other types to and from instances of a Double that represent an object's length.

public ref class LengthConverter : System::ComponentModel::TypeConverter

public class LengthConverter : System.ComponentModel.TypeConverter

type LengthConverter = class
    inherit TypeConverter

Public Class LengthConverter
Inherits TypeConverter

Inheritance: Object

TypeConverter
LengthConverter

Examples

The following example shows how to create and use an instance of the LengthConverter object. A custom method called ChangeLeft is defined, which converts the content of a ListBoxItem (defined in a separate Extensible Application Markup Language (XAML) file) to an instance of Double, and later into a String. This method passes the ListBoxItem to a LengthConverter object, which converts the ListBoxItem Content to an instance of Double. Notice that this value has already been converted to a String by using the ToString method. This value is then passed back to the SetLeft method and the GetLeft method of the Canvas in order to change the position of the text1 object.

private void ChangeLeft(object sender, SelectionChangedEventArgs args)
{
    ListBoxItem li = ((sender as ListBox).SelectedItem as ListBoxItem);
    LengthConverter myLengthConverter = new LengthConverter();
    Double db1 = (Double)myLengthConverter.ConvertFromString(li.Content.ToString());
    Canvas.SetLeft(text1, db1);
    String st1 = (String)myLengthConverter.ConvertToString(Canvas.GetLeft(text1));
    canvasLeft.Text = "Canvas.Left = " + st1;
}

Private Sub ChangeLeft(ByVal sender As Object, ByVal e As SelectionChangedEventArgs)
    Dim li As ListBoxItem = CType(CType(sender, ListBox).SelectedItem, ListBoxItem)
    Dim myLengthConverter As New LengthConverter
    Dim db1 As Double = CType(myLengthConverter.ConvertFromString(li.Content.ToString()), Double)
    Canvas.SetLeft(text1, db1)
    Dim st1 As String = CType(myLengthConverter.ConvertToString(Canvas.GetLeft(text1)), String)
    canvasLeft.Text = "Canvas.Left = " + st1
End Sub

Remarks

LengthConverter supports conversion to and from the following types: String, Decimal, Single, Double, Int16, Int32, Int64, UInt16, UInt32, and UInt64.

Constructors

LengthConverter()

Initializes a new instance of the LengthConverter class.

Methods

CanConvertFrom(ITypeDescriptorContext, Type)	Determines whether conversion is possible from a specified type to a Double that represents an object's length.
CanConvertFrom(Type)	Returns whether this converter can convert an object of the given type to the type of this converter. (Inherited from TypeConverter)
CanConvertTo(ITypeDescriptorContext, Type)	Determines whether conversion is possible to a specified type from a Double that represents an object's length.
CanConvertTo(Type)	Returns whether this converter can convert the object to the specified type. (Inherited from TypeConverter)
ConvertFrom(ITypeDescriptorContext, CultureInfo, Object)	Converts instances of other data types into instances of Double that represent an object's length.
ConvertFrom(Object)	Converts the given value to the type of this converter. (Inherited from TypeConverter)
ConvertFromInvariantString(ITypeDescriptorContext, String)	Converts the given string to the type of this converter, using the invariant culture and the specified context. (Inherited from TypeConverter)
ConvertFromInvariantString(String)	Converts the given string to the type of this converter, using the invariant culture. (Inherited from TypeConverter)
ConvertFromString(ITypeDescriptorContext, CultureInfo, String)	Converts the given text to an object, using the specified context and culture information. (Inherited from TypeConverter)
ConvertFromString(ITypeDescriptorContext, String)	Converts the given text to an object, using the specified context. (Inherited from TypeConverter)
ConvertFromString(String)	Converts the specified text to an object. (Inherited from TypeConverter)
ConvertTo(ITypeDescriptorContext, CultureInfo, Object, Type)	Converts other types into instances of Double that represent an object's length.
ConvertTo(Object, Type)	Converts the given value object to the specified type, using the arguments. (Inherited from TypeConverter)
ConvertToInvariantString(ITypeDescriptorContext, Object)	Converts the specified value to a culture-invariant string representation, using the specified context. (Inherited from TypeConverter)
ConvertToInvariantString(Object)	Converts the specified value to a culture-invariant string representation. (Inherited from TypeConverter)
ConvertToString(ITypeDescriptorContext, CultureInfo, Object)	Converts the given value to a string representation, using the specified context and culture information. (Inherited from TypeConverter)
ConvertToString(ITypeDescriptorContext, Object)	Converts the given value to a string representation, using the given context. (Inherited from TypeConverter)
ConvertToString(Object)	Converts the specified value to a string representation. (Inherited from TypeConverter)
CreateInstance(IDictionary)	Re-creates an Object given a set of property values for the object. (Inherited from TypeConverter)
CreateInstance(ITypeDescriptorContext, IDictionary)	Creates an instance of the type that this TypeConverter is associated with, using the specified context, given a set of property values for the object. (Inherited from TypeConverter)
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
GetConvertFromException(Object)	Returns an exception to throw when a conversion cannot be performed. (Inherited from TypeConverter)
GetConvertToException(Object, Type)	Returns an exception to throw when a conversion cannot be performed. (Inherited from TypeConverter)
GetCreateInstanceSupported()	Returns whether changing a value on this object requires a call to the CreateInstance(IDictionary) method to create a new value. (Inherited from TypeConverter)
GetCreateInstanceSupported(ITypeDescriptorContext)	Returns whether changing a value on this object requires a call to CreateInstance(IDictionary) to create a new value, using the specified context. (Inherited from TypeConverter)
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetProperties(ITypeDescriptorContext, Object, Attribute[])	Returns a collection of properties for the type of array specified by the value parameter, using the specified context and attributes. (Inherited from TypeConverter)
GetProperties(ITypeDescriptorContext, Object)	Returns a collection of properties for the type of array specified by the value parameter, using the specified context. (Inherited from TypeConverter)
GetProperties(Object)	Returns a collection of properties for the type of array specified by the value parameter. (Inherited from TypeConverter)
GetPropertiesSupported()	Returns whether this object supports properties. (Inherited from TypeConverter)
GetPropertiesSupported(ITypeDescriptorContext)	Returns whether this object supports properties, using the specified context. (Inherited from TypeConverter)
GetStandardValues()	Returns a collection of standard values from the default context for the data type this type converter is designed for. (Inherited from TypeConverter)
GetStandardValues(ITypeDescriptorContext)	Returns a collection of standard values for the data type this type converter is designed for when provided with a format context. (Inherited from TypeConverter)
GetStandardValuesExclusive()	Returns whether the collection of standard values returned from GetStandardValues() is an exclusive list. (Inherited from TypeConverter)
GetStandardValuesExclusive(ITypeDescriptorContext)	Returns whether the collection of standard values returned from GetStandardValues() is an exclusive list of possible values, using the specified context. (Inherited from TypeConverter)
GetStandardValuesSupported()	Returns whether this object supports a standard set of values that can be picked from a list. (Inherited from TypeConverter)
GetStandardValuesSupported(ITypeDescriptorContext)	Returns whether this object supports a standard set of values that can be picked from a list, using the specified context. (Inherited from TypeConverter)
GetType()	Gets the Type of the current instance. (Inherited from Object)
IsValid(ITypeDescriptorContext, Object)	Returns whether the given value object is valid for this type and for the specified context. (Inherited from TypeConverter)
IsValid(Object)	Returns whether the given value object is valid for this type. (Inherited from TypeConverter)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
SortProperties(PropertyDescriptorCollection, String[])	Sorts a collection of properties. (Inherited from TypeConverter)
ToString()	Returns a string that represents the current object. (Inherited from Object)

Applies to

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