[Drozh]

Можно вот так:

Код:

function ParseStr(const Source: String): String;
var
 Posit: Integer;
 Dest: String;
begin
 Dest := LowerCase(Source);

 Posit := Pos('http://', Dest)+Length('http://');
 Dest := Copy(Dest, 1, Posit-1)+'content.'+Copy(Dest, Posit, Length(Dest));

 Posit := Pos('.html', Dest);
 Delete(Dest, Posit, Length(Dest));

  for Posit := Length(Dest) downto 1 do
   if Dest[Posit] = '/' then
   begin
    Dest := Copy(Dest, 1, Posit)+'v-'+Copy(Dest, Posit+1, Length(Dest))+'.flv';
    Break;
   end;

 Result := Dest;
end;