asp.net mvc 3 - Razor skipping nested foreach loops -

in database have string of child tables. in razor view trying loop through ultimate parent , filter collection few levels down.

i have got work using following extract:

@foreach (var artist in model) {     <tr>         <td>             @html.displayfor(modelitem => artist.artistname)         </td>     </tr>      foreach (var album in artist.albums)     {         foreach (var song in album.songs)         {             if (song.songplays != null)             {                 foreach (var songplay in song.songplays)                 {             <tr>         <td>              @html.displayfor(a => songplay.playtime)         </td>     </tr>                 }             }         }     } } 

the issue cannot sort whole child collection playtime. solve tried working skipping out preceding foreach loops using:

    foreach (var songplay in artist.albums.selectmany(a => a.songs.selectmany(b => b.songplays)))     {     <tr>         <td>             @html.displayfor(a => songplay.playtime)         </td>     </tr>     } 

this seems work without filter applied in controller action, returns null result when filter applied. have tried checking in view if result null, not work - like:

if (artist.albums.select(a => a.songs.select(b => b.songplays)) != null)     {         foreach (var songplay in artist.albums.selectmany(a => a.songs.selectmany(b => b.songplays)))         { ... 

i still null result, presuming null check not doing hoping do.

so if can give me guidance either on whether approach sensible , if can null check on grandchild collection somehow, or if there better approach, appreciated.

i'm not sure right. far understand need filter null items , second code sample in question ok in terms of orderting. in case, may add where clause selection:

foreach (var songplay in artist.albums.selectmany(a => a.songs.where(b => b != null).selectmany(b => b.songplays))) {     <tr>         <td>             @html.displayfor(a => songplay.playtime)         </td>     </tr> }