c# - ListBox not posting to MVC controller -

i have form have text area's , listbox. other fields in form being posted controller not listbox?

here razor code:

 <form method="post" action="/admin/addpost">     @html.validationsummary(true)     <div class="form-group">         <label>title</label>         <input type="text" class="form-control" name="blogtitle" placeholder="title" value="@model.blogtitle" required>     </div>     <div class="form-group">         <label>image</label>         <input type="text" class="form-control" name="blogimage" value="@model.blogimage" placeholder="image">     </div>     <div class="form-group">         <label>description</label>         <textarea name="blogdescription">@model.blogdescription</textarea>     </div>     <div class="form-group">         <label>tags</label>         @html.listbox("tags", model.tags, new { @class = "form-control", @name = "tags", @multiple = "multiple" })     </div>     <button type="submit" class="btn btn-primary">save</button> </form> 

here , post controller:

 public actionresult addpost()     {         var model = new blogmodel         {             blogtitle = string.empty,             blogdescription = string.empty,             blogimage = string.empty,             tags = new tagqueries().getalltags().select(x => new selectlistitem             {                 text = x.tagname,                 value = x.tagid.tostring(),                 selected = false             })         };         return view(model);     }     [httppost]     public actionresult addpost(blogmodel model)     {         transferblogdetailstodbmodel addtodb = new transferblogdetailstodbmodel();         if (modelstate.isvalid && model != null)         {             try             {                 addtodb.transferblogdetails(model);                 return redirecttoaction("index", "admin");             }             catch (exception)             {                 modelstate.addmodelerror("", "invalid data,please try again");             }         }         return view(model);     } 

here model:

public class blogmodel {     [hiddeninput]     public int blogid { get; set; }      [required(errormessage = "blog title required")]     public string blogtitle { get; set; }     [required(errormessage = "blog description required")]     public string blogdescription { get; set; }     public string blogimage { get; set; }      public ienumerable<selectlistitem> tags { get; set; } } 

any suggestions appreciated.

your property tags typeof ienumerable<selectlistitem> , cannot bind <select multiple> collection of complex objects. <select> posts array of simple values (the values of selected options).

your model needs property bind to, say

public ienumerable<int> selectedtags { get; set; } 

assuming tagid of tag typeof int. code in view is

 @html.listboxfor(m => m.selectedtags , model.tags, new { @class = "form-control" }) 

side notes:

1. do not use new { @name = "..." } - fortunately nothing, , never attempt override name attribute generated htmlhelper methods
2. do not use new { @multiple = "multiple" } - listbox() , listboxfor() methods generate that
3. use textboxfor() andtextareafor()` methods generate other form controls correct 2-way model binding
4. remove selected = false code in selectlistitem constructor (not false default, value ignored anyway - value of selectedtags determines selected)