---
title: "The CampaignDefinitionID method"
slug: "the-campaigndefinitionid-method"
abstract: "Overview of the CampaignDefinitionID method and properties with example."
---
# The CampaignDefinitionID method

To define the campaign definition ID property for the `Campaign` event, use the `CampaignDefinitionId()` method.

| Property | Details |
| --- | --- |
| UT SDK method | `CampaignDefinitionId (string)` |
| Required/optional | Optional |
| Multiple invocations | Multiple invocations are forbidden and cause an *InvalidOperationException* exception |
| Value validation | Must contain a proper item ID value |

For example:

```text
var campaignEvent = UTRequestBuilder.CampaignEvent("01f8ffbf-d662-4a87-beee-413307055c48")

```