In your view, try this:
@ {
var cultureItems = LocOptions.Value.SupportedUICultures
.Select(c => new SelectListItem { Value = c.Name, Text = c.TwoLetterISOLanguageName })
.ToList();
}
<li class="nav-item dropdown">
<a class="nav-link dropdown-toggle waves-effect waves-light" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Dropdown title
</a>
<div class="dropdown-menu" aria-labelledby="navbarDropdown">
@foreach (var culture in cultureItems)
{
<form id="selectLanguage" asp-controller="Home"
asp-action="SetLanguage" asp-route-returnUrl="@Context.Request.Path"
method="post" class="form-horizontal" role="form">
<input class="dropdown-item waves-effect waves-light" type="submit" name="culture" value="@culture.Value" />
</form>
}
</div>
</li>