ItemMetadataSchema Class
Represents the metadata schema for an item, including how to identify an item and its version information, and how change units are defined.
Assembly: Microsoft.Synchronization.SimpleProviders (in Microsoft.Synchronization.SimpleProviders.dll)
The ItemMetadataSchema type exposes the following members.
| Name | Description | |
|---|---|---|
![]() | ItemMetadataSchema(IEnumerable<CustomFieldDefinition>, IEnumerable<IdentityRule>) | Initializes a new instance of the ItemMetadataSchema class that contains information about custom fields and how to identify an item. |
![]() | ItemMetadataSchema(IEnumerable<CustomFieldDefinition>, IEnumerable<IdentityRule>, IEnumerable<ChangeUnitVersionDefinition>) | Initializes a new instance of the ItemMetadataSchema class that contains information about custom fields, how to identify an item, and how change units are defined. |
| Name | Description | |
|---|---|---|
![]() | ChangeUnitVersionDefinitions | Gets a collection of ChangeUnitVersionDefinition objects that represent the way in which a change unit is identified in terms of an ID, an ID format, and a set of fields that define a change unit's version. |
![]() | CustomFields | Gets a collection of CustomFieldDefinition objects that each represent a custom field. Fields can be used to identify an item in the metadata or store version information about an item. |
![]() | IdentityRules | Gets a collection of IdentityRule objects that defines the way in which an item is identified within a replica. |
Sync Framework maps item store data, or additional metadata that you create, to internal metadata store IDs and versions by using an ItemMetadataSchema object that is exposed by the MetadataSchema property. For more information about simple provider metadata, see Managing Metadata for Simple Providers.
The following code examples provide input for the ItemMetadataSchema object. The constants in the sample code define an integer value for each column in the item store. These values are used when creating the custom field definitions and identity rules for the ItemMetadataSchema object. To view this code in the context of a complete application, see the "Sync101 using Simple Sync Provider" application that is available in the Sync Framework SDK and from Code Gallery.
public const uint CUSTOM_FIELD_ID = 1; public const uint CUSTOM_FIELD_TIMESTAMP = 2;
public override ItemMetadataSchema MetadataSchema { get { CustomFieldDefinition[] customFields = new CustomFieldDefinition[2]; customFields[0] = new CustomFieldDefinition(CUSTOM_FIELD_ID, typeof(ulong)); customFields[1] = new CustomFieldDefinition(CUSTOM_FIELD_TIMESTAMP, typeof(ulong)); IdentityRule[] identityRule = new IdentityRule[1]; identityRule[0] = new IdentityRule(new uint[] { CUSTOM_FIELD_ID }); return new ItemMetadataSchema(customFields, identityRule); } }
Public Const CUSTOM_FIELD_ID As UInteger = 1 Public Const CUSTOM_FIELD_TIMESTAMP As UInteger = 2
Public Overrides ReadOnly Property MetadataSchema() As ItemMetadataSchema Get Dim customFields As CustomFieldDefinition() = New CustomFieldDefinition(1) {} customFields(0) = New CustomFieldDefinition(CUSTOM_FIELD_ID, GetType(ULong)) customFields(1) = New CustomFieldDefinition(CUSTOM_FIELD_TIMESTAMP, GetType(ULong)) Dim identityRule As IdentityRule() = New IdentityRule(0) {} identityRule(0) = New IdentityRule(New UInteger() {CUSTOM_FIELD_ID}) Return New ItemMetadataSchema(customFields, identityRule) End Get End Property
