c# - difference between uploadfile and uploadfilewithuniquename in WebRequestMethods.Ftp -

two questions here :

1)difference between webrequestmethods.ftp.uploadfile , webrequestmethods.ftp.uploadfilewithuniquename?

2)when upload file using code below existing file override file.and safe assume override?

         public static void main ()     {         // object used communicate server.         ftpwebrequest request = (ftpwebrequest)webrequest.create("ftp://www.contoso.com/test.htm");           request.method = webrequestmethods.ftp.uploadfile;  // if use  request.method = webrequestmethods.ftp.uploadfilewithuniquename;            // example assumes ftp site uses anonymous logon.         request.credentials = new networkcredential ("anonymous","janedoe@contoso.com");          // copy contents of file request stream.         streamreader sourcestream = new streamreader("testfile.txt");         byte [] filecontents = encoding.utf8.getbytes(sourcestream.readtoend());         sourcestream.close();         request.contentlength = filecontents.length;          stream requeststream = request.getrequeststream();         requeststream.write(filecontents, 0, filecontents.length);         requeststream.close();          ftpwebresponse response = (ftpwebresponse)request.getresponse();          console.writeline("upload file complete, status {0}", response.statusdescription);          response.close();         } 

these methods refer ftp commands stor , stou.

if logged in user has privs, stor (webrequestmethods.ftp.uploadfile) create new file or overwrite existing file.