c# - Asp.Net - IEnumerable properties not binding to model -

i nullpointerexception error when attempt render @model.columns in view. i'm using linqtoexcel.

relevant code parts:

model:

namespace steer.models {     public class upfile     {         // irrelevant properties (name,size,filetype) omitted          public ienumerable<string> columns { get; set; }         public ienumerable<linqtoexcel.row> rows { get; set; }          public class upfiledbcontext : dbcontext         {             public dbset<upfile> upfiles { get; set; }         }      } } 

view:

  @model steer.models.upfile    @foreach (var item in model.columns)   {      <th>@item</th>   } 

controller:

upfile = new upfile(); // name, size, filetype binding omitted  // here attempt bind columns , rows uploaded excel file var excel = new excelqueryfactory(appdomain.currentdomain.basedirectory + "uploaded\\" + up.name); var firstsheet = excel.getworksheetnames().first(); // rows ienumerable up.rows = c in excel.worksheet(firstsheet)     select c; // getcolumnnames returns list. up.columns property ienumerable. up.columns = excel.getcolumnnames(firstsheet); db.upfiles.add(up); db.savechanges(); 

name, size, filetype set fine. columns , rows properties empty.

the extraction of excel file works fine, can directly send excel rows view. when try reference properties have troubles.

// get: files/details/5 public actionresult details(int? id) {     if (id == null)     {         return new httpstatuscoderesult(httpstatuscode.badrequest);     }     upfile upfile = db.upfiles.find(id);     if (upfile == null)     {         return httpnotfound();     }     return view(upfile); } 

also!! when insert breakpoint @ db.savechanges(), data there