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--- title: Use .NET to manage properties and metadata for a blob container titleSuffix: Azure Storage description: Learn how to set and retrieve system properties and store custom metadata on blob containers in your Azure Storage account using the .NET client library. services: storage author: stevenmatthew ms.author: shaas ms.service: azure-blob-storage ms.topic: how-to ms.date: 08/05/2024 ms.devlang: csharp ms.custom: devx-track-csharp, devguide-csharp, devx-track-dotnet # Customer intent: As a .NET developer, I want to manage properties and custom metadata for blob containers, so that I can efficiently control additional data attributes and enhance data organization in my Azure Storage account. --- # Manage container properties and metadata with .NET [!INCLUDE [storage-dev-guide-selector-manage-properties-container](../../../includes/storage-dev-guides/storage-dev-guide-selector-manage-properties-container.md)] Blob containers support system properties and user-defined metadata, in addition to the data they contain. This article shows how to manage system properties and user-defined metadata with the [Azure Storage client library for .NET](/dotnet/api/overview/azure/storage). [!INCLUDE [storage-dev-guide-prereqs-dotnet](../../../includes/storage-dev-guides/storage-dev-guide-prereqs-dotnet.md)] ## Set up your environment [!INCLUDE [storage-dev-guide-project-setup-dotnet](../../../includes/storage-dev-guides/storage-dev-guide-project-setup-dotnet.md)] #### Authorization The authorization mechanism must have the necessary permissions to work with container properties or metadata. For authorization with Microsoft Entra ID (recommended), you need Azure RBAC built-in role **Storage Blob Data Reader** or higher for the *get* operations, and **Storage Blob Data Contributor** or higher for the *set* operations. To learn more, see the authorization guidance for [Get Container Properties (REST API)](/rest/api/storageservices/get-container-properties#authorization), [Set Container Metadata (REST API)](/rest/api/storageservices/set-container-metadata#authorization), or [Get Container Metadata (REST API)](/rest/api/storageservices/get-container-metadata#authorization). ## About properties and metadata - **System properties**: System properties exist on each Blob storage resource. Some of them can be read or set, while others are read-only. Under the covers, some system properties correspond to certain standard HTTP headers. The Azure Storage client library for .NET maintains these properties for you. - **User-defined metadata**: User-defined metadata consists of one or more name-value pairs that you specify for a Blob storage resource. You can use metadata to store additional values with the resource. Metadata values are for your own purposes only, and do not affect how the resource behaves. Metadata name/value pairs are valid HTTP headers and should adhere to all restrictions governing HTTP headers. For more information about metadata naming requirements, see [Metadata names](/rest/api/storageservices/naming-and-referencing-containers--blobs--and-metadata#metadata-names). ## Retrieve container properties To retrieve container properties, call one of the following methods: - [GetProperties](/dotnet/api/azure.storage.blobs.blobcontainerclient.getproperties) - [GetPropertiesAsync](/dotnet/api/azure.storage.blobs.blobcontainerclient.getpropertiesasync) The following code example fetches a container's system properties and writes some property values to a console window: :::code language="csharp" source="~/azure-storage-snippets/blobs/howto/dotnet/dotnet-v12/Metadata.cs" id="Snippet_ReadContainerProperties"::: ## Set and retrieve metadata You can specify metadata as one or more name-value pairs on a blob or container resource. To set metadata, add name-value pairs to an [IDictionary](/dotnet/api/system.collections.idictionary) object, and then call one of the following methods to write the values: - [SetMetadata](/dotnet/api/azure.storage.blobs.blobcontainerclient.setmetadata) - [SetMetadataAsync](/dotnet/api/azure.storage.blobs.blobcontainerclient.setmetadataasync) The following code example sets metadata on a container. :::code language="csharp" source="~/azure-storage-snippets/blobs/howto/dotnet/dotnet-v12/Metadata.cs" id="Snippet_AddContainerMetadata"::: To retrieve metadata, call one of the following methods: - [GetProperties](/dotnet/api/azure.storage.blobs.blobcontainerclient.getproperties) - [GetPropertiesAsync](/dotnet/api/azure.storage.blobs.blobcontainerclient.getpropertiesasync) Then, read the values, as shown in the example below. :::code language="csharp" source="~/azure-storage-snippets/blobs/howto/dotnet/dotnet-v12/Metadata.cs" id="Snippet_ReadContainerMetadata"::: ## Resources To learn more about setting and retrieving container properties and metadata using the Azure Blob Storage client library for .NET, see the following resources. ### REST API operations The Azure SDK for .NET contains libraries that build on top of the Azure REST API, allowing you to interact with REST API operations through familiar .NET paradigms. The client library methods for setting and retrieving properties and metadata use the following REST API operations: - [Get Container Properties](/rest/api/storageservices/get-container-properties) (REST API) - [Set Container Metadata](/rest/api/storageservices/set-container-metadata) (REST API) - [Get Container Metadata](/rest/api/storageservices/get-container-metadata) (REST API) The `GetProperties` and `GetPropertiesAsync` methods retrieve container properties and metadata by calling both the [Get Blob Properties](/rest/api/storageservices/get-blob-properties) operation and the [Get Blob Metadata](/rest/api/storageservices/get-blob-metadata) operation. [!INCLUDE [storage-dev-guide-resources-dotnet](../../../includes/storage-dev-guides/storage-dev-guide-resources-dotnet.md)] [!INCLUDE [storage-dev-guide-next-steps-dotnet](../../../includes/storage-dev-guides/storage-dev-guide-next-steps-dotnet.md)]