add tagsbyresource ui element

Author: tfitzmac

articles/managed-applications/media/managed-application-elements/microsoft.common.tagsbyresource.png

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+---
+title: Azure TagsByResource UI element
+description: Describes the Microsoft.Common.TagsByResource UI element for Azure portal. Use to apply tags to a resource during deployment.
+author: tfitzmac
+
+ms.service: managed-applications
+ms.topic: reference
+ms.date: 11/11/2019
+ms.author: tomfitz
+
+---
+
+# Microsoft.Common.TagsByResource UI element
+
+A control for associating [tags](../azure-resource-manager/resource-group-using-tags.md) with the resources in a deployment.
+
+## UI sample
+
+![Microsoft.Common.DropDown](./media/managed-application-elements/microsoft.common.tagsbyresource.png)
+
+## Schema
+
+```json
+{
+  "name": "element1",
+  "type": "Microsoft.Common.TagsByResource",
+  "resources": [
+    "Microsoft.Storage/storageAccounts",
+    "Microsoft.Compute/virtualMachines"
+  ]
+}
+```
+
+## Sample output
+
+```json
+{
+  "Microsoft.Storage/storageAccounts": {
+    "Dept": "Finance",
+    "Environment": "Production"
+  },
+  "Microsoft.Compute/virtualMachines": {
+    "Dept": "Finance"
+  }
+}
+```
+
+## Remarks
+
+- At least one item in the `resources` array must be specified.
+- Each element in `resources` must be a fully qualified resource type. Elements included here appear in the **Resource** dropdown. The user can apply tags to any resources in the dropdown.
+- The output of the control is formatted for easy assignment of tag values in an Azure Resource Manager template. To receive the control's output in a template, include a parameter as shown in the following example:
+
+  ```json
+  "parameters": {
+    "tagsByResource": { "type": "object", "defaultValue": {} }
+  }
+  ```
+
+  And for each resource that can be tagged, include a tags property that accesses the parameter values for that type:
+
+  ```json
+  {
+    "name": "saName1",
+    "type": "Microsoft.Storage/storageAccounts",
+    "tags": "[ if(contains(parameters('tagsByResource'), 'Microsoft.Storage/storageAccounts'), parameters('tagsByResource')['Microsoft.Storage/storageAccounts'], json('{}')) ]",
+    ...
+  ```
+
+- Use the [if](../azure-resource-manager/resource-group-template-functions-logical.md#if) function when accessing the tagsByResource parameter. It enables you to assign an empty object when no tags are assigned to the given resource type.
+
+## Next steps
+
+- For an introduction to creating UI definitions, see [Getting started with CreateUiDefinition](create-uidefinition-overview.md).
+- For a description of common properties in UI elements, see [CreateUiDefinition elements](create-uidefinition-elements.md).