order by and file.exist() c#

Question

I have file list which sorting by file length, and progress files. The question is when progress takes a long time, some files in the list may be deleted, moved or can be changed, and I get the error
how can ı use order by and if file.exist() [check file is still there] method for this or any kind of solution?

var sort = from fn in filelist
           orderby new FileInfo(fn).Length ascending
           select fn;

foreach(string n in sort)
{
    //progress
}

Thanks

filelist has file's address

Answer 1

Use File.Exists method this way :

   var sort = from fn in filelist
               where File.Exists(fn)
               orderby new FileInfo(fn).Length ascending
               select fn;