Autocomplete
!
View 
@Html.AutoCompleteFor(model => model.Id, new PeopleDatalist())
Datalist
!
View 
@Html.DatalistFor(model => model.Id, new PeopleDatalist())
Multi datalist
!
View 
@Html.DatalistFor(model => model.Ids, new PeopleDatalist() { Multi = true })
Javascript 
document.getElementById('button').addEventListener('click', function() {
    var datalist = new MvcDatalist(document.querySelector('.datalist'));
    datalist.set({ readonly: !datalist.readonly });
});