ExpandableObjectConverter Class

Definition

Namespace:

System.ComponentModel

Assembly:

System.ComponentModel.TypeConverter.dll

Source:

ExpandableObjectConverter.cs

Provides a type converter to convert expandable objects to and from various other representations.

public ref class ExpandableObjectConverter : System::ComponentModel::TypeConverter

public class ExpandableObjectConverter : System.ComponentModel.TypeConverter

type ExpandableObjectConverter = class
    inherit TypeConverter

Public Class ExpandableObjectConverter
Inherits TypeConverter

Inheritance

Object

TypeConverter

ExpandableObjectConverter

Derived

System.Drawing.IconConverter

System.Drawing.Printing.MarginsConverter

System.Windows.Forms.ColumnHeaderConverter

System.Windows.Forms.ListViewItemConverter

System.Windows.Xps.Serialization.ColorTypeConverter

System.Windows.Xps.Serialization.FontTypeConverter

System.Windows.Xps.Serialization.ImageSourceTypeConverter

Examples

The following code example converts a variable of type Margins to a string variable.

String^ strM = "1,2,3,4";
System::Drawing::Printing::Margins^ m = gcnew System::Drawing::Printing::Margins( 1,2,3,4 );
Console::WriteLine( TypeDescriptor::GetConverter( strM )->CanConvertTo( System::Drawing::Printing::Margins::typeid ) );
Console::WriteLine( TypeDescriptor::GetConverter( m )->ConvertToString( m ) );

string strM="1,2,3,4";
System.Drawing.Printing.Margins  m= new System.Drawing.Printing.Margins(1,2,3,4);
Console.WriteLine(TypeDescriptor.GetConverter(strM).CanConvertTo(typeof(System.Drawing.Printing.Margins))); 
Console.WriteLine(TypeDescriptor.GetConverter(m).ConvertToString(m));

Dim strM As String
strM = "1,2,3,4"
            Dim m As New System.Drawing.Printing.Margins(1, 2, 3, 4)
Console.WriteLine(TypeDescriptor.GetConverter(strM).CanConvertTo(GetType(System.Drawing.Printing.Margins)))
Console.WriteLine(TypeDescriptor.GetConverter(m).ConvertToString(m))

The following code example demonstrates how to use the NotifyParentPropertyAttribute and the ExpandableObjectConverter class to create an expandable property on a custom control. This code example is part of a larger example provided for the NotifyParentPropertyAttribute class.

[TypeConverter(typeof(BorderAppearanceConverter))]
public class BorderAppearance
{
    private int borderSizeValue = 1;
    private Color borderColorValue = Color.Empty;

    [Browsable(true),
    NotifyParentProperty(true),
    EditorBrowsable(EditorBrowsableState.Always),
    DefaultValue(1)]
    public int BorderSize
    {
        get
        {
            return borderSizeValue;
        }
        set
        {
            if (value < 0)
            {
                throw new ArgumentOutOfRangeException(
                    "BorderSize",
                    value,
                    "must be >= 0");
            }

            if (borderSizeValue != value)
            {
                borderSizeValue = value;
            }
        }
    }

    [Browsable(true)]
    [NotifyParentProperty(true)]
    [EditorBrowsable(EditorBrowsableState.Always)]
    [DefaultValue(typeof(Color), "")]
    public Color BorderColor
    {
        get
        {
            return borderColorValue;
        }
        set
        {
            if (value.Equals(Color.Transparent))
            {
                throw new NotSupportedException("Transparent colors are not supported.");
            }

            if (borderColorValue != value)
            {
                borderColorValue = value;
            }
        }
    }
}

<TypeConverter(GetType(BorderAppearanceConverter))>  _
Public Class BorderAppearance
    Private borderSizeValue As Integer = 1
    Private borderColorValue As Color = Color.Empty
    
    
    <Browsable(True), NotifyParentProperty(True), EditorBrowsable(EditorBrowsableState.Always), DefaultValue(1)>  _
    Public Property BorderSize() As Integer 
        Get
            Return borderSizeValue
        End Get
        Set
            If value < 0 Then
                Throw New ArgumentOutOfRangeException("BorderSize", value, "must be >= 0")
            End If
            
            If borderSizeValue <> value Then
                borderSizeValue = value
            End If
        End Set
    End Property
    
    
    <Browsable(True), NotifyParentProperty(True), EditorBrowsable(EditorBrowsableState.Always), DefaultValue(GetType(Color), "")>  _
    Public Property BorderColor() As Color 
        Get
            Return borderColorValue
        End Get
        Set
            If value.Equals(Color.Transparent) Then
                Throw New NotSupportedException("Transparent colors are not supported.")
            End If
            
            If borderColorValue <> value Then
                borderColorValue = value
            End If
        End Set
    End Property
End Class

Remarks

This class adds support for properties on an object to the methods and properties provided by TypeConverter. To make a type of property expandable in the PropertyGrid, specify this TypeConverter for standard implementations of GetPropertiesSupported and GetProperties. Mark child properties with the NotifyParentPropertyAttribute to ensure correct behavior in a PropertyGrid control.

Note

You should never access a type converter directly. Instead, call the appropriate converter by using TypeDescriptor. For more information, see the examples in the TypeConverter base class.

For more information about type converters, see the TypeConverter base class and How to: Implement a Type Converter.

Constructors

ExpandableObjectConverter()

Initializes a new instance of the ExpandableObjectConverter class.

Methods

CanConvertFrom(ITypeDescriptorContext, Type)	Returns whether this converter can convert an object of the given type to the type of this converter, using the specified context. (Inherited from TypeConverter)
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)	Returns whether this converter can convert the object to the specified type, using the specified context. (Inherited from TypeConverter)
CanConvertTo(Type)	Returns whether this converter can convert the object to the specified type. (Inherited from TypeConverter)
ConvertFrom(ITypeDescriptorContext, CultureInfo, Object)	Converts the given object to the type of this converter, using the specified context and culture information. (Inherited from TypeConverter)
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 the given value object to the specified type, using the specified context and culture information. (Inherited from TypeConverter)
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[])	Gets a collection of properties for the type of object specified by the value parameter.
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)	Gets a value indicating whether this object supports properties using the specified context.
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)

See also

• NotifyParentPropertyAttribute