c# - Using RenderPartial to assign Model Property values -

i new mvc platform , trying simple application hold of framework,

application:i designing admin application has form enter question , multiple options database, have viewmodel called "questionviewmodel" has properties "quesiton" , list of optionsviewmodel in it, "optionviewmodel" consists of "option" , "isrightanswer" properties, on ui, have questionview displays textbox question , want question have 4 options, created partialview called "questionoptionview" takes "optionviewmodel" model, loop 4 times through partialview , display textbox "option" , "isrightasnwer" radiobutton,

the ui displays tetsbox "question" , 4 other "textboxes" entering "options", when post form, "options" not bind viewmodel

how can achieve model binding these partialview data main viewmodel??

public class questionviewmodel {     [display(name = "enter question")]     public string question { get; set; }     public ilist<questionoptionviewmodel> options { get; set; }     public int maxoptions { { return 4; } }      public questionviewmodel()     {         options = new list<questionoptionviewmodel>();     } }  public class questionoptionviewmodel {     public string option { get; set; }     public bool isrightanswer { get; set; } } 

in viewm have below,

    @using (html.beginrouteform("savequestion", new {}, formmethod.post)){      <div>         @html.labelfor(m => m.question)         @html.textboxfor(m => m.question)     </div>      <p>add options question</p>      (int = 0; < model.maxoptions; i++)     {         { html.renderpartial("questionoption", new babbi_test_admin.models.questionoptionviewmodel()); }     }      <input type="submit" value="save" /> 

when form submitted have post method as,

    [httppost]     public void savequestion(questionviewmodel viewmodel)     {      } 

my viewmodel in post has "options" null

this happening cause must binding questionviewmodel action of controller instead, need create viewmodel have questionviewmodel optionviewmodel

error

[httppost] public void savequestion(questionviewmodel viewmodel) {  } 

in post method expecting questionviewmodel how can expect optionviewmodel

another thing renbdering partial view questionoptionviewmodel contains options , right answer in loop right answer 4 thing incorrect.

sample

public class questionviewmodel {    //properties } public class optionviewmodel {    //properties }  public class questionandoptionviewmodel {   // questionviewmodel , optionviewmodel model object   //constructors   //methods }  [httppost] public void savequestion(questionandoptionviewmodel viewmodel) {     //your code here; }