# FolderDataUnion

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

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

Union for folder type -specific data in FolderData.

- **Full name:** `MFiles.FolderDataUnion`
- **Proto file:** [`mfiles/structs.proto`](https://developer.m-files.com/APIs/gRPC-API/downloads/proto/mfiles/structs.proto)
- **Nested types:** [`FolderDataUnion.UnknownFolderDataData`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.FolderDataUnion/index.md#t-UnknownFolderDataData), [`FolderDataUnion.ViewFolderData`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.FolderDataUnion/index.md#t-ViewFolderData), [`FolderDataUnion.ExternalViewFolderData`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.FolderDataUnion/index.md#t-ExternalViewFolderData)

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## Fields

| Field | Type | Number | Description |
|---|---|---|---|
| <a id="f-view_folder"></a>`view_folder` | [`FolderDataUnion.ViewFolderData`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.FolderDataUnion/index.md#t-ViewFolderData) (oneof data) | 2 |   |
| <a id="f-external_view_folder"></a>`external_view_folder` | [`FolderDataUnion.ExternalViewFolderData`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.FolderDataUnion/index.md#t-ExternalViewFolderData) (oneof data) | 6 |   |

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## Used in fields

- [`FolderData.data`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.FolderData/index.md#f-data): Additional folder type -specific data as a union.

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## Nested message UnknownFolderDataData

Full name: `MFiles.FolderDataUnion.UnknownFolderDataData`

No fields.

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## Nested message ViewFolderData

Full name: `MFiles.FolderDataUnion.ViewFolderData`

| Field | Type | Number | Description |
|---|---|---|---|
| <a id="t-ViewFolderData-view"></a>`view` | [`View`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.View/index.md) | 1 | The view. |

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## Nested message ExternalViewFolderData

Full name: `MFiles.FolderDataUnion.ExternalViewFolderData`

| Field | Type | Number | Description |
|---|---|---|---|
| <a id="t-ExternalViewFolderData-external_view"></a>`external_view` | [`ExternalView`](https://developer.m-files.com/APIs/gRPC-API/Reference/Messages/MFiles.ExternalView/index.md) | 1 | The external view. |