javascript - How to select object in dropdown -

i have city class

public class city {     public int id { get; set; }     public string name { get; set; }     public string countrycode { get; set; } } 

and ride class.

public class ride {     public guid id { get; set; }     public city { get; set; }     public list<city> { get; set; }     public datetime dateandtime { get; set; } }     

what best way load cities, pass view, show them in dropdownlists , post data controller? best if add more 1 city to column. have found selectize.js have no experience javascript. can pass options json etc or list of cities database.

thank time.

you'll need view model, if want select multiple cities @ once. example:

public class rideviewmodel {     public guid id { get; set; }     public datetime dateandtime { get; set; }      public int fromcityid { get; set; }     public list<int> tocityids { get; set; }     public ienumerable<selectlistitem> citychoices { get; set; } } 

notice there's no list<city> property on view model. instead, there's tocityids store selected id values list box , citychoices used populate list box. can't post full city objects list box, simple types int. so, on post you'll use values tocityids lookup city instances database. same goes from property on entity.

now, in controller:

private void populatecitychoices(rideviewmodel model) {     model.citychoices = db.cities.select(m => new selectlistitem     {         value = m.id,         text = m.name     }); }  public actionresult create() {     var model = new rideviewmodel();     populatecitychoices(model);     return view(model); }  [httppost] public actionresult create(rideviewmodel model) {     if (modelstate.isvalid)     {         // create new `ride` , map data on model         var ride = new ride         {             id = guid.newguid(),             dateandtime = model.dateandtime,             = db.cities.find(model.fromcityid),             = db.cities.where(m => m.tocityids.contains(m.id))         }         db.rides.add(ride);         db.savechanges();     }      // must repopulate `citychoices` after post if need return form     // view again due error.     populatecitychoices(model);     return view(model); } 

finally in view change model declaration to:

@model namespace.to.rideviewmodel 

and add from select list , to list box:

@html.dropdownlistfor(m => m.fromcityid, model.citychoices)  @html.listboxfor(m => m.tocityids, model.citychoices) 

you can use same choices both, since they're both selecting cities.