Populating a treeview with files in ASP.NET C# -

i have treeview trying populate folders , files. treeview populating folders fine not files. here code:

protected void page_load(object sender, eventargs e)         {              if (!ispostback)             {                 populatetree();             }                        }  private void populatetree()         {             //populate tree based on subfolders of specified virtualimageroot             var rootfolder = new directoryinfo(virtualimageroot);             var root = addnodeanddescendents(rootfolder, null);              //add root treeview             treeview1.nodes.add(root);         }  private treenode addnodeanddescendents(directoryinfo folder, treenode parentnode)         {             //add treenode, displaying folder's name , storing full path folder value...             string virtualfolderpath;              if (parentnode == null)             {                 virtualfolderpath = virtualimageroot;             }             else             {                 virtualfolderpath = parentnode.value + folder.name + "/";             }              var node = new treenode(folder.name, virtualfolderpath);              //recurse through folder's subfolders             var subfolders = folder.getdirectories();              foreach (directoryinfo subfolder in subfolders)             {                 var child = addnodeanddescendents(subfolder, node);                  foreach (fileinfo file in subfolder.getfiles())                 {                      var index = file.fullname.lastindexof(@"\", stringcomparison.ordinal);                     var strname = file.fullname.substring(index + 1);                     var name = strname.split('.');                      var tn = new treenode();                     if (name.length > 1 && name[1].tolower() == "bch")                     {                         tn = new treenode(name[0], file.fullname);                     }                     else                     {                         tn = new treenode(name[0], file.fullname);                     }                     child.childnodes.add(tn);                 }                 node.childnodes.add(child);              }             //return new treenode             return node;         } 

here tree looks like:

here picture of files in folder:

i trying show files type .bch, along folders in treeview. can please tell me doing wrong?

the problem code didn't take account first level of folder hierarchy:

private void populatetree() {     var rootfolder = new directoryinfo(@"c:\inetpub\wwwroot\yourwebproject");     var root = addnodeanddescendents(rootfolder);     treeview1.nodes.add(root); }  private treenode addnodeanddescendents(directoryinfo folder) {             var node = new treenode(folder.name, folder.name);      var subfolders = folder.getdirectories();      foreach (directoryinfo subfolder in subfolders)     {         var child = addnodeanddescendents(subfolder);         node.childnodes.add(child);     }      foreach (fileinfo file in folder.getfiles("*.bch"))     {         var tn = new treenode(file.name, file.fullname);         node.childnodes.add(tn);     }     return node; }