Adding divider when programmatically creating Office UI Fabric IContextualMenuItem[]

Question

When declaratively creating Context menu items, you can add divider using

  <li class="ms-ContextualMenu-item ms-ContextualMenu-item--divider"></li>

How to add it when programmatically creating array of IContextualMenuItems?

Solution

Use itemType: ContextualMenuItemType.Divider, like this

const items: IContextualMenuItem[] = [];
items.push( {
    key: "divider1",
    itemType: ContextualMenuItemType.Divider
} );