C#简单的写日志方法

private object o=new object ();
private static string getFiles()
{
//判断路径、文件是否存在，如不存在则生成相关资源
string dir = AppDomain.CurrentDomain.BaseDirectory + @"log\";
if (!Directory.Exists(dir))
{
Directory.CreateDirectory(dir);
}
//设置文件名
string currtime = DateTime.Now.ToString("yyyyMM");
dir += currtime + ".log";
if (!File.Exists(dir))
{
FileStream fs = File.Create(dir);
fs.Close();
}
return dir;
}
//写日志
private static void log(string logstr)
{
lock (o)
{
string dir = getFiles();
StreamWriter sw = new StreamWriter(dir, true);
sw.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss") + " " + logstr);
sw.Close();
}
}