how to add incident field values into thread text

Summary

add incident field values into thread text

Content

Hi ,

Plz let me know how to add Field values into Thread text.

$parent_inc and $inc_tmp are two objects.

                          $f_count = count($parent_inc->Threads);
                            $parent_inc->Threads[$f_count] = new RNCPHP\Thread();
                            $parent_inc->Threads[$f_count]->EntryType = new RNCPHP\NamedIDOptList();  
                            $parent_inc->Threads[$f_count]->EntryType->LookupName = 'Staff Account';  
                            $parent_inc->Threads[$f_count]->ContentType->ID=2;           

//this red color code giving me error   

             
                            $parent_inc->Threads[$f_count]->Text = "This Incident was closed and merged into "   . $inc_tmp.ReferenceNumber . " - " . $inc_tmp.Subject ;