.NET Framework Class Library
CollectionDataContractAttribute Class

When applied to a collection type, enables custom specification of the collection item elements. This attribute can be applied only to types that are recognized by the DataContractSerializer as valid, serializable collections.

Inheritance Hierarchy
SystemObject
   SystemAttribute
    System.Runtime.SerializationCollectionDataContractAttribute

Namespace:   System.Runtime.Serialization
Assembly:  System.Runtime.Serialization (in System.Runtime.Serialization.dll)
Syntax
<[%$TOPIC/ms585141_en-us_VS_110_3_0_0_0_0%]([%$TOPIC/ms585141_en-us_VS_110_3_0_0_0_1%].Class Or [%$TOPIC/ms585141_en-us_VS_110_3_0_0_0_2%].Struct, Inherited := False,  _
	AllowMultiple := False)> _
Public NotInheritable Class CollectionDataContractAttribute _
	Inherits [%$TOPIC/ms585141_en-us_VS_110_3_0_0_0_3%]
[[%$TOPIC/ms585141_en-us_VS_110_3_0_1_0_0%]([%$TOPIC/ms585141_en-us_VS_110_3_0_1_0_1%].Class|[%$TOPIC/ms585141_en-us_VS_110_3_0_1_0_2%].Struct, Inherited = false, 
	AllowMultiple = false)]
public sealed class CollectionDataContractAttribute : [%$TOPIC/ms585141_en-us_VS_110_3_0_1_0_3%]
[[%$TOPIC/ms585141_en-us_VS_110_3_0_2_0_0%]([%$TOPIC/ms585141_en-us_VS_110_3_0_2_0_1%]::Class|[%$TOPIC/ms585141_en-us_VS_110_3_0_2_0_2%]::Struct, Inherited = false, 
	AllowMultiple = false)]
public ref class CollectionDataContractAttribute sealed : public [%$TOPIC/ms585141_en-us_VS_110_3_0_2_0_3%]
[<[%$TOPIC/ms585141_en-us_VS_110_3_0_3_0_0%]>]
[<[%$TOPIC/ms585141_en-us_VS_110_3_0_3_0_1%]([%$TOPIC/ms585141_en-us_VS_110_3_0_3_0_2%].Class|[%$TOPIC/ms585141_en-us_VS_110_3_0_3_0_3%].Struct, Inherited = false, 
    AllowMultiple = false)>]
type CollectionDataContractAttribute =  
    class 
        inherit [%$TOPIC/ms585141_en-us_VS_110_3_0_3_0_4%] 
    end

The CollectionDataContractAttribute type exposes the following members.

Constructors
  NameDescription
Public method Supported by Portable Class Library Supported in .NET for Windows Store apps CollectionDataContractAttributeInitializes a new instance of the CollectionDataContractAttribute class.
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Properties
  NameDescription
Public property Supported by Portable Class Library Supported in .NET for Windows Store apps IsReferenceGets or sets a value that indicates whether to preserve object reference data.
Public property Supported by Portable Class Library Supported in .NET for Windows Store apps ItemNameGets or sets a custom name for a collection element.
Public property Supported by Portable Class Library Supported in .NET for Windows Store apps KeyNameGets or sets the custom name for a dictionary key name.
Public property Supported by Portable Class Library Supported in .NET for Windows Store apps NameGets or sets the data contract name for the collection type.
Public property Supported by Portable Class Library Supported in .NET for Windows Store apps NamespaceGets or sets the namespace for the data contract.
Public property TypeIdWhen implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)
Public property Supported by Portable Class Library Supported in .NET for Windows Store apps ValueNameGets or sets the custom name for a dictionary value name.
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Methods
  NameDescription
Public method Supported by Portable Class Library Supported in .NET for Windows Store apps EqualsInfrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)
Public method Supported by Portable Class Library Supported in .NET for Windows Store apps GetHashCodeReturns the hash code for this instance. (Inherited from Attribute.)
Public method Supported by Portable Class Library Supported in .NET for Windows Store apps GetTypeGets the Type of the current instance. (Inherited from Object.)
Public method IsDefaultAttributeWhen overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.)
Public method MatchWhen overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Public method Supported by Portable Class Library Supported in .NET for Windows Store apps ToStringReturns a string that represents the current object. (Inherited from Object.)
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Explicit Interface Implementations
  NameDescription
Explicit interface implemetation Private method _AttributeGetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetation Private method _AttributeGetTypeInfoRetrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetation Private method _AttributeGetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetation Private method _AttributeInvokeProvides access to properties and methods exposed by an object. (Inherited from Attribute.)
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Remarks

The CollectionDataContractAttribute is intended to ease interoperability when working with data from non-WCF providers and to control the exact shape of serialized instances. To this end, the ItemName property enables you to control the names of the repeating items inside a collection. This is especially useful when the provider does not use the XML element type name as the array item name, for example, if a provider uses "String" as an element type name instead of the XSD type name "string".

The CollectionDataContractAttribute is also intended to be used with dictionary types to handle keyed collections. Dictionary types are classes that implement either the IDictionary or the IDictionaryTKey, TValue interface, for example, the DictionaryTKey, TValue. Use the KeyName and ValueName properties to set custom names when using the DictionaryTKey, TValue class.

For more information about using the DataContractSerializer, see Using Data Contracts.

Examples

The following example applies the CollectionDataContractAttribute to a class that inherits from the ListT class. The code sets the Name and ItemName properties to custom values.

	<CollectionDataContract(Name := "Custom{0}List", ItemName := "CustomItem")> _
	Public Class CustomList(Of T)
		Inherits List(Of T)
		Public Sub New()
			MyBase.New()
		End Sub 

		Public Sub New(ByVal items() As T)
			MyBase.New()
			For Each item As T In items
				Add(item)
			Next item
		End Sub 
	End Class
[CollectionDataContract(Name = "Custom{0}List", ItemName = "CustomItem")]
public class CustomList<T> : List<T>
{
    public CustomList()
        : base()
    {
    }

    public CustomList(T[] items)
        : base()
    {
        foreach (T item in items)
        {
            Add(item);
        }
    }
}

When the ServiceModel Metadata Utility Tool (Svcutil.exe) is used to generate code for the client, the code resembles the following example. Notice that the name of the class is changed, as well as the ItemName. When using generics, the type parameter name is used to create the resulting type name.

	' This is the generated code. Note that the class is renamed to "CustomBookList",  
	' and the ItemName is set to "CustomItem".
	<System.CodeDom.Compiler.GeneratedCodeAttribute("System.Runtime.Serialization", "3.0.0.0"), System.Runtime.Serialization.CollectionDataContractAttribute(ItemName := "CustomItem")> _
	Public Class CustomBookList
		Inherits System.Collections.Generic.List(Of Microsoft.Security.Samples.Book)
	End Class
// This is the generated code. Note that the class is renamed to "CustomBookList", 
// and the ItemName is set to "CustomItem".
[System.CodeDom.Compiler.GeneratedCodeAttribute("System.Runtime.Serialization", "3.0.0.0")]
[System.Runtime.Serialization.CollectionDataContractAttribute(ItemName = "CustomItem")]
public class CustomBookList : System.Collections.Generic.List<Microsoft.Security.Samples.Book>
{
}
Version Information

.NET Framework

Supported in: 4.5.1, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1
Platforms

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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.