ASP.NET MVC 4 Create method has null object -

i have problem creating object don't know why. have null object in parameter in post create method , in modelstate error:

{system.invalidoperationexception: parameter conversion type 'system.string' type 'blanskomenu.models.actionoffer' failed because no type converter can convert between these types. @ system.web.mvc.valueproviderresult.convertsimpletype(cultureinfo culture, object value, type destinationtype) @ system.web.mvc.valueproviderresult.unwrappossiblearraytype(cultureinfo culture, object value, type destinationtype) @ system.web.mvc.valueproviderresult.convertto(type type, cultureinfo culture) @ system.web.mvc.defaultmodelbinder.convertproviderresult(modelstatedictionary modelstate, string modelstatekey, valueproviderresult valueproviderresult, type destinationtype)}

these methods in controller:

    //     // get: /action/      public actionresult index()     {         var offers = _repository.getallactionoffers();         return view(offers);     }      //     // get: /action/create      public actionresult create()     {         return view();     }      //     // post: /action/create      [httppost]     public actionresult create(actionoffer action)     {         try         {             if (modelstate.isvalid)             {                 _repository.createactionoffer(action);                 return redirecttoaction("index");             }             return view(action);         }         catch         {             return view(action);         }     } 

this actionoffer model:

public class actionoffer {     [key]     public int id { get; set; }     public string text { get; set; }     public string title { get; set; }     public string imagepath { get; set; }     [datatype(datatype.date)]     public datetime startdate { get; set; }     [datatype(datatype.date)]     public datetime enddate { get; set; } } 

and create view:

@model blanskomenu.models.actionoffer  @{     viewbag.title = "vytvořit akční nabídku";     layout = "~/views/shared/_layout.cshtml"; }  <h2>vytvořit akční nabídku</h2>  @using (html.beginform()) {     @html.antiforgerytoken()     @html.validationsummary(true)      <fieldset>         <legend>akční nabídka</legend>          @html.hiddenfor(model => model.id)          <div class="editor-label">             @html.labelfor(model => model.title)         </div>         <div class="editor-field">             @html.editorfor(model => model.title)             @html.validationmessagefor(model => model.title)         </div>          <div class="editor-label">             @html.labelfor(model => model.text)         </div>         <div class="editor-field">             @html.editorfor(model => model.text)             @html.validationmessagefor(model => model.text)         </div>          <div class="editor-label">             @html.labelfor(model => model.imagepath)         </div>         <div class="editor-field">             @html.editorfor(model => model.imagepath)             @html.validationmessagefor(model => model.imagepath)         </div>          <div class="editor-label">             @html.labelfor(model => model.startdate)         </div>         <div class="editor-field">             @html.editorfor(model => model.startdate)             @html.validationmessagefor(model => model.startdate)         </div>          <div class="editor-label">             @html.labelfor(model => model.enddate)         </div>         <div class="editor-field">             @html.editorfor(model => model.enddate)             @html.validationmessagefor(model => model.enddate)         </div>         <p>             <input type="submit" value="save" />         </p>     </fieldset> }  <div>     @html.actionlink("back list", "index") </div>  @section scripts {     @scripts.render("~/bundles/jqueryval") } 

thanks help

try changing

public actionresult create(actionoffer action) 

to

public actionresult create(actionoffer actionoffer)