c# - Unable to bind MVC model property to input element -

i'm having trouble getting model bind input box created custom helper method. wrapped jquery ajax-driven autocomplete box helper method called "html.autocompleteboxajax." helper creates element javascript autocomplete functionality.

the property in model string called "formatname". have verified that, in generated html view, both name , id of input element "formatname", , there no other elements identities. i've checked model has default constructor, , "formatname" property publicly accessible. lastly, i've verified when channel model passed view, channel.formatname has correct value. yet despite this, can't value bind element, , input box remains blank. there no binding when going other way, view controller, , channel.formatname remains blank.

what missing? somehow because i'm using custom helper method?

model:

namespace webapp.models {     public class channelmodel     {         xyz.dataaccess.ods.db db = config.db();          public string id { get; set; }          // parent project         [display(name = "project")]         public string projectid { get; set; }          // format name         [required(errormessage = "format required.")]         [regularexpression(constants.username_regex, errormessage = constants.username_regexerrormsg)]         [display(name = "format")]         public string formatname { get; set; }          // channel name         [required(errormessage="channel name required.")]         [stringlength(100, errormessage = constants.minlengtherrormsg, minimumlength = constants.username_minlength)]         [regularexpression(constants.username_regex, errormessage = constants.username_regexerrormsg)]         [display(name = "channel name")]         public string name { get; set; }          // sequence         [display(name = "sequence")]         public string sequenceid { get; set; }          public channelmodel()         {             id = guid.newguid().tostring();         }          public channelmodel(xyz.dataaccess.ods.channel channel_db)         {             id = channel_db.id;             projectid = channel_db.project_id;             name = channel_db.name;             formatname = channel_db.format_name;             sequenceid = channel_db.sequence_id;         }          public xyz.dataaccess.ods.channel builddbobject()         {             xyz.dataaccess.ods.channel channel = new xyz.dataaccess.ods.channel();             channel.id = id;             channel.project_id = projectid;             channel.name = name;             channel.format_name = formatname;             channel.sequence_id = sequenceid;             return channel;         }     }   } 

view

@model webapp.models.channelmodel @using helpermethods.infrastructure  @{     viewbag.title = "edit";      var sequences = viewdata["sequences"] list<selectlistitem>; }  <h2>edit</h2>  <script src="@url.content("~/scripts/jquery.validate.min.js")" type="text/javascript"></script> <script src="@url.content("~/scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>  @section header { }  @using (html.beginform()) {     @html.validationsummary(true)     <fieldset>         <legend>channel</legend>          @html.hiddenfor(model => model.id)         @html.hiddenfor(model => model.projectid)         @html.hiddenfor(model => model.name)          <div class="editor-field">             @html.labelfor(model => model.name):             @html.displayfor(model => model.name)         </div>          <div class="editor-label">             @html.label("format")         </div>         <div class="editor-field">             @html.autocompleteboxajax("formatname", url.action("getformatsbeginningwith"))             @html.validationmessagefor(model => model.formatname)         </div>          <!-- sequence -->         <div class="editor-label">             @html.label("sequence")         </div>         <div class="editor-field">             @html.slavedropdownlist("sequenceid", "groupid", url.action("getsequencesingroup"), webapp.util.makeselectlist(sequences, model.sequenceid))         </div>           <p>             <input type="submit" value="save" />         </p>     </fieldset> }  <div>     @html.actionlink("back list", "index") </div> 

controller

namespace webapp.controllers {     public class channelcontroller : infrastructure.nocachecontroller     {         xyz.dataaccess.ods.db db = config.db();          -- stuff --          [httpget]         public actionresult getformatsbeginningwith(string term)         {             var formats = db.getformatsbeginningwith(term);              list<customhelpers.autocompleteitem> items = new list<customhelpers.autocompleteitem>();             foreach (var format in formats)                 items.add(new customhelpers.autocompleteitem { value = format.name, label = format.name });              var j = json(items, jsonrequestbehavior.allowget);             return j;         }           public actionresult edit(string id)         {             channelmodel channelmodel = new channelmodel(db.getchannel(id));              string groupid = db.getproject(channelmodel.projectid).group_id;             var sequences = db.getsequencesingroup(groupid);             viewdata["sequences"] = makeselectlistitems(sequences);              return view(channelmodel);         }          //         // post: /channel/edit/5          [httppost]         public actionresult edit(channelmodel model)         {             if (modelstate.isvalid)             {                 db.updatechannel(model.builddbobject());                  return redirecttoaction("index");             }              string groupid = db.getproject(model.projectid).group_id;              var sequences = db.getsequencesingroup(groupid);             viewdata["sequences"] = makeselectlistitems(sequences);              return view(model);         }          -- more stuff --     } } 

helper method autocompletebox

    public static mvchtmlstring autocompleteboxajax(this htmlhelper html, string id, string actionurl)     {         tagbuilder input = new tagbuilder("input");         input.attributes.add("id", id);         input.attributes.add("name", id);         input.attributes.add("type", "text");         input.addcssclass("autocomplete_ajax");         input.attributes.add("value", "");         input.attributes.add("action", actionurl);          var variables = new dictionary<string, string>() {             {"autocomplete_id", id}         };          var script = populatescripttemplate("template_autocomplete_ajax.js", variables);          stringbuilder s = new stringbuilder();         s.appendline(input.tostring(tagrendermode.selfclosing));         s.appendline(script);          return new mvchtmlstring(s.tostring());     } 

javascript autocomplete

$('#autocomplete_id').autocomplete({     source: $('#autocomplete_id').attr('action')     }); 

relevant portion of view's html

<div class="editor-field">     <input action="/channel/getformatsbeginningwith" class="autocomplete_ajax" id="formatname" name="formatname" type="text" value="" />     <span class="field-validation-valid" data-valmsg-for="formatname" data-valmsg-replace="true"></span> </div> 

answer turned out simple input @jakub. helper has populate value; there's no automatic binding takes place html helpers. once took care of this, auto binding of posts controller worked expected.