C#Stopwatch用法

框架：.net core2.0

class Program
{
static void Main(string[] args)
{
Fun();
}
public static void Fun() {
Stopwatch stopwatch = new Stopwatch();
stopwatch.Start();
for (var i = 1; i < 1000000000; i++) {
//doSomeString
}
stopwatch.Stop();
Console.WriteLine(stopwatch.ElapsedMilliseconds);
}
}