TypeDescriptor.GetProperties Method (Object, Attribute())


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Returns the collection of properties for a specified component using a specified array of attributes as a filter.

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

Public Shared Function GetProperties (
	component As Object,
	attributes As Attribute()
) As PropertyDescriptorCollection


Type: System.Object

A component to get the properties for.

Type: System.Attribute()

An array of type Attribute to use as a filter.

Return Value

Type: System.ComponentModel.PropertyDescriptorCollection

A PropertyDescriptorCollection with the properties that match the specified attributes for the specified component.

Exception Condition

component is a cross-process remoted object.

The properties for the component parameter can differ from the properties of a class, because the site can add or remove properties if the component parameter is sited.

The attributes parameter array is used to filter the array. Filtering is defined by the following rules:

  • If a property does not have an Attribute of the same class, the property is not included in the returned array.

  • If the attribute is an instance of the Attribute class, the property must be an exact match or it is not included in the returned array.

  • If an Attribute instance is specified and it is the default property, it is included in the returned array even if there is no instance of the Attribute in the property.

  • If attributes has a default attribute, the GetProperties method matches the case when the property does not have the attribute applied.

If component is null, an empty collection is returned.

The order of the returned collection is not guaranteed to be identical between calls, so always order it before use.

The following code example demonstrates how to implement the GetProperties method. This code example is part of a larger example provided for the PropertyTab class.

' Returns the properties of the specified component extended with 
' a CategoryAttribute reflecting the name of the type of the property.
Public Overloads Overrides Function GetProperties(ByVal component As Object, ByVal attributes() As System.Attribute) As System.ComponentModel.PropertyDescriptorCollection
    Dim props As PropertyDescriptorCollection
    If attributes Is Nothing Then
        props = TypeDescriptor.GetProperties(component)
        props = TypeDescriptor.GetProperties(component, attributes)
    End If
    Dim propArray(props.Count - 1) As PropertyDescriptor
    Dim i As Integer
    For i = 0 To props.Count - 1
        ' Create a new PropertyDescriptor from the old one, with 
        ' a CategoryAttribute matching the name of the type.
        propArray(i) = TypeDescriptor.CreateProperty(props(i).ComponentType, props(i), New CategoryAttribute(props(i).PropertyType.Name))
    Next i
    Return New PropertyDescriptorCollection(propArray)
End Function

Public Overloads Overrides Function GetProperties(ByVal component As Object) As System.ComponentModel.PropertyDescriptorCollection
    Return Me.GetProperties(component, Nothing)
End Function

.NET Framework
Available since 1.1
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