# MetadataStructureItem

Location: [gRPC API](https://developer.m-files.com/APIs/gRPC-API/index.md) > [Reference](https://developer.m-files.com/APIs/gRPC-API/Reference/index.md) > [Enums](https://developer.m-files.com/APIs/gRPC-API/Reference/Enums/index.md)

HTML version: https://developer.m-files.com/APIs/gRPC-API/Reference/Enums/MFiles.MetadataStructureItem/

- **Full name:** `MFiles.MetadataStructureItem`
- **Proto file:** [`mfiles/enums.proto`](https://developer.m-files.com/APIs/gRPC-API/downloads/proto/mfiles/enums.proto)

<a id="values"></a>

## Values

| Name | Number | Description |
|---|---|---|
| <a id="v-METADATA_STRUCTURE_ITEM_NONE"></a>`METADATA_STRUCTURE_ITEM_NONE` | 0 | None. |
| <a id="v-METADATA_STRUCTURE_ITEM_OBJECT_TYPE"></a>`METADATA_STRUCTURE_ITEM_OBJECT_TYPE` | 1 | Object type. |
| <a id="v-METADATA_STRUCTURE_ITEM_PROPERTY_DEF"></a>`METADATA_STRUCTURE_ITEM_PROPERTY_DEF` | 2 | Property def. |
| <a id="v-METADATA_STRUCTURE_ITEM_OBJECT_CLASS"></a>`METADATA_STRUCTURE_ITEM_OBJECT_CLASS` | 3 | Class. |
| <a id="v-METADATA_STRUCTURE_ITEM_WORKFLOW"></a>`METADATA_STRUCTURE_ITEM_WORKFLOW` | 4 | Workflow. |
| <a id="v-METADATA_STRUCTURE_ITEM_STATE"></a>`METADATA_STRUCTURE_ITEM_STATE` | 5 | State. |
| <a id="v-METADATA_STRUCTURE_ITEM_NAMED_ACL"></a>`METADATA_STRUCTURE_ITEM_NAMED_ACL` | 6 | Named ACL. |
| <a id="v-METADATA_STRUCTURE_ITEM_USER"></a>`METADATA_STRUCTURE_ITEM_USER` | 7 | User. |
| <a id="v-METADATA_STRUCTURE_ITEM_USER_GROUP"></a>`METADATA_STRUCTURE_ITEM_USER_GROUP` | 8 | User group. |
| <a id="v-METADATA_STRUCTURE_ITEM_CLASS_GROUP"></a>`METADATA_STRUCTURE_ITEM_CLASS_GROUP` | 9 | Class group. |
| <a id="v-METADATA_STRUCTURE_ITEM_VIEW_DEF"></a>`METADATA_STRUCTURE_ITEM_VIEW_DEF` | 10 | View definition. |
| <a id="v-METADATA_STRUCTURE_ITEM_LANGUAGE"></a>`METADATA_STRUCTURE_ITEM_LANGUAGE` | 11 | Language. |
| <a id="v-METADATA_STRUCTURE_ITEM_ACL"></a>`METADATA_STRUCTURE_ITEM_ACL` | 12 | An access control list. |
| <a id="v-METADATA_STRUCTURE_ITEM_VALUE_LIST_ITEM"></a>`METADATA_STRUCTURE_ITEM_VALUE_LIST_ITEM` | 13 | Value list item. |
| <a id="v-METADATA_STRUCTURE_ITEM_VALUE_LIST"></a>`METADATA_STRUCTURE_ITEM_VALUE_LIST` | 14 | Value list. |
| <a id="v-METADATA_STRUCTURE_ITEM_EVENT_HANDLER"></a>`METADATA_STRUCTURE_ITEM_EVENT_HANDLER` | 15 | Vault-specific event handler. |
| <a id="v-METADATA_STRUCTURE_ITEM_STATE_TRANSITION"></a>`METADATA_STRUCTURE_ITEM_STATE_TRANSITION` | 16 | State transition. |
| <a id="v-METADATA_STRUCTURE_ITEM_METADATA_CARD_CONFIGURATION"></a>`METADATA_STRUCTURE_ITEM_METADATA_CARD_CONFIGURATION` | 17 | Metadata card configuration. |
| <a id="v-METADATA_STRUCTURE_ITEM_ALL"></a>`METADATA_STRUCTURE_ITEM_ALL` | 10000 | All item types. DO NOT use this for mapping. |

<a id="used-by-methods"></a>

## Used by methods

- [IRPCVault.GetAllMetadataStructureItemIdswithAliases](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetAllMetadataStructureItemIdswithAliases/index.md): Gets all unambiguous alias-to-ID mappings of one kind of metadata structure item, or of all kinds, as typed lists.
- [IRPCVault.GetMetadataStructureItemIdByAlias](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdByAlias/index.md): Finds the vault-specific ID of a metadata structure item from one of its aliases.
- [IRPCVault.GetMetadataStructureItemIdByGUID](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdByGUID/index.md): Finds the vault-specific ID of a metadata structure item (object type, property definition, class, workflow, ...) from its GUID.
- [IRPCVault.GetMetadataStructureItemIdsByAliases](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdsByAliases/index.md): Gets all unambiguous alias-to-ID mappings of one kind of metadata structure item, or of all kinds, as JSON.
- [IRPCVault.GetMetadataStructureItemIdsByAliases_Compressed](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdsByAliases_Compressed/index.md): Gets alias-to-ID mappings of several kinds of metadata structure item as JSON, with the option to exclude kinds.

<a id="used-in-fields"></a>

## Used in fields

- [`ExportStructureItem.type`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.ExportStructureItem/index.md#f-type): Metadata structure item type.
- [`MetadataStructureContext.context_type`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.MetadataStructureContext/index.md#f-context_type): The structure element type of the context.
- [`MetadataStructureItemArray.value`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.MetadataStructureItemArray/index.md#f-value): An array of the MetadataStructureItem values.
- [`MetadataStructureNamedReference.reference_type`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.MetadataStructureNamedReference/index.md#f-reference_type): The structure element type.
- [`MetadataStructureSelector.item_type`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.MetadataStructureSelector/index.md#f-item_type): Metadata structure item type to select.
- [`GetMetadataStructureItemIdByGUIDRequest.item_type`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdByGUID/index.md#request): The kind of item to look for. The method description lists the supported values.
- [`GetMetadataStructureItemIdByAliasRequest.item_type`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdByAlias/index.md#request): The kind of item to look for. The method description lists the supported values.
- [`GetMetadataStructureItemIdsByAliasesRequest.emsi`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdsByAliases/index.md#request): The kind of item, or `METADATA_STRUCTURE_ITEM_ALL` for every kind that can have aliases.
- [`GetMetadataStructureItemIdsByAliases_CompressedRequest.msi_array_included`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetMetadataStructureItemIdsByAliases_Compressed/index.md#request): The kinds of item to return. A single `METADATA_STRUCTURE_ITEM_ALL` means every kind that can have aliases.
- [`GetAllMetadataStructureItemIdswithAliasesRequest.emsi`](https://developer.m-files.com/APIs/gRPC-API/Reference/MFiles.IRPCVault/GetAllMetadataStructureItemIdswithAliases/index.md#request): The kind of item, or `METADATA_STRUCTURE_ITEM_ALL` for every kind that can have aliases.