namespace ConsoleApp1
{
class Program
{
static void Main(string[] args)
{
using(StreamReader reader = new StreamReader(@"d:\test.txt", Encoding.GetEncoding(1251)))
using(StreamWriter writer = new StreamWriter(@"d:\test.txt", false, Encoding.UTF8))
{
writer.Write(reader.ReadToEnd());
}
}
}
}
спасибо