ant-design-blazor/components/menu/MenuDivider.razor

@namespace AntDesign
@inherits AntDomComponentBase

<li Class="@ClassMapper.Class"></li>

@code {
    [CascadingParameter]
    public Menu RootMenu { get; set; }

    private void setClass()
    {        
        ClassMapper.Clear()
            .Add($"{RootMenu.PrefixCls}-item-divider");            
    }

    protected override void OnInitialized()
    {
        setClass();
        base.OnInitialized();
    }

}