c#文件的读写

//写
using (FileStream fs = File.Create(filename))
{
　　byte[] info = new UTF8Encoding(true).GetBytes("This is some text in the file.");
　　fs.Write(info, 0, info.Length);
}

//读
using (StreamReader sr = File.OpenText(filename))
{
　　string s = "";
　　while ((s = sr.ReadLine()) != null)
　　{
　　　　DisplayAlert("read", s, "");
　　}
}