private void AddFileToDocumentLibrary(string documentLibraryUrl, string filename, byte[] file_bytes, string itemTitleText)     {         SPSecurity.RunWithElevatedPrivileges(delegate()         {             using (SPSite site = new SPSite(documentLibraryUrl))             {                 using (SPWeb web = site.OpenWeb())                 {                     web.AllowUnsafeUpdates = true;                     SPDocumentLibrary documentLibrary = (SPDocumentLibrary)web.Lists["MyDocumentLibraryName"];                     SPFileCollection files = documentLibrary.RootFolder.Files;                     SPFile newFile = files.Add(documentLibrary.RootFolder.Url + "/" + filename, file_bytes, true);                      SPList documentLibraryAsList = web.Lists["MyDocumentLibraryName"];                     SPListItem itemJustAdded = documentLibraryAsList.GetItemById(newFile.ListItemAllFields.ID);                     SPContentType documentContentType = documentLibraryAsList.ContentTypes["Document"]; //amend with your document-derived custom Content Type                     itemJustAdded["ContentTypeId"] = documentContentType.Id;                     itemJustAdded["Title"] = itemTitleText;                     //set other propeerties here..                     itemJustAdded.Update();                     newFile.CheckIn("New", SPCheckinType.OverwriteCheckIn);                     web.AllowUnsafeUpdates = false;                 }             }         });     }