C# 写文件的几种方式。

string fileName = Path.Combine(LogPath, "log.txt");
Directory.CreateDirectory(LogPath);//创建了文件夹之后，才能创建里面的文件
using (FileStream fileStream = File.Create(fileName))//打开文件流 （创建文件并写入）
{
    string name = "12345567778890";
    byte[] bytes = Encoding.Default.GetBytes(name);
    fileStream.Write(bytes, 0, bytes.Length);
    fileStream.Flush();
}
using (FileStream fileStream = File.Create(fileName))//打开文件流 （创建文件并写入）
{
    StreamWriter sw = new StreamWriter(fileStream);
    sw.WriteLine("1234567890");
    sw.Flush();
}

using (StreamWriter sw = File.AppendText(fileName))//流写入器（创建/打开文件并写入）
{
    string msg = "15663353135";
    sw.WriteLine(msg);
    sw.Flush();
}
using (StreamWriter sw = File.AppendText(fileName))//流写入器（创建/打开文件并写入）
{
    string name = "0987654321";
    byte[] bytes = Encoding.Default.GetBytes(name);
    sw.BaseStream.Write(bytes, 0, bytes.Length);
    sw.Flush();
}

File 直接写入
string name = "0987654321";
byte[] bytes = Encoding.Default.GetBytes(name);
File.WriteAllBytes(path, bytes);