CollectionDataContractAttribute Class

Definition

Namespace:

System.Runtime.Serialization

Assembly:

System.Runtime.Serialization.Primitives.dll

Source:

CollectionDataContractAttribute.cs

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.

public ref class CollectionDataContractAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Struct, AllowMultiple=false, Inherited=false)]
public sealed class CollectionDataContractAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Struct, AllowMultiple=false, Inherited=false)>]
type CollectionDataContractAttribute = class
    inherit Attribute

Public NotInheritable Class CollectionDataContractAttribute
Inherits Attribute

Inheritance

Object

Attribute

CollectionDataContractAttribute

Attributes

AttributeUsageAttribute

Examples

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

[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);
        }
    }
}

<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

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 : System.Collections.Generic.List<Microsoft.Security.Samples.Book>
{
}

' 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

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 IDictionary<TKey,TValue> interface, for example, the Dictionary<TKey,TValue>. Use the KeyName and ValueName properties to set custom names when using the Dictionary<TKey,TValue> class.

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

Constructors

CollectionDataContractAttribute()

Initializes a new instance of the CollectionDataContractAttribute class.

Properties

IsItemNameSetExplicitly	Gets whether ItemName has been explicitly set.
IsKeyNameSetExplicitly	Gets whether KeyName has been explicitly set.
IsNameSetExplicitly	Gets whether Name has been explicitly set.
IsNamespaceSetExplicitly	Gets whether Namespace has been explicitly set.
IsReference	Gets or sets a value that indicates whether to preserve object reference data.
IsReferenceSetExplicitly	Gets whether reference has been explicitly set.
IsValueNameSetExplicitly	Gets whether ValueName has been explicitly set.
ItemName	Gets or sets a custom name for a collection element.
KeyName	Gets or sets the custom name for a dictionary key name.
Name	Gets or sets the data contract name for the collection type.
Namespace	Gets or sets the namespace for the data contract.
TypeId	When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute)
ValueName	Gets or sets the custom name for a dictionary value name.

Methods

Equals(Object)	Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute)
GetHashCode()	Returns the hash code for this instance. (Inherited from Attribute)
GetType()	Gets the Type of the current instance. (Inherited from Object)
IsDefaultAttribute()	When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute)
Match(Object)	When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute)
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
ToString()	Returns a string that represents the current object. (Inherited from Object)

See also

• DataContractSerializer