Program.cs

using  System.Runtime.CompilerServices;

Test();

void Test(){
    TraceMessage("HelloWorld"); //（1）
    TraceMessage("HelloWorld"); //（2）
}

void TraceMessage(string message,
        [CallerMemberName] string memberName = "",
        [CallerFilePath] string sourceFilePath = "",
        [CallerLineNumber] int sourceLineNumber = 0)
{
    Console.WriteLine("message: " + message);
    Console.WriteLine("member name: " + memberName);
    Console.WriteLine("source file path: " + sourceFilePath);
    Console.WriteLine("source line number: " + sourceLineNumber);
}

// 同步
// Console.WriteLine("调用 DoSomethingSync 之前");
// DoSomethingSync();
// Console.WriteLine("调用 DoSomethingSync 之后");

// void DoSomethingSync(){
//     Thread.Sleep(1000);
//     Console.WriteLine("等我一秒钟");
// }

// 异步

// Console.WriteLine("调用 DoSomethingAsync 之前");
// Task task = DoSomethingAsync();
// Console.WriteLine("调用 DoSomethingAsync 之后");
// await task;

// async Task DoSomethingAsync(){
//     Task delay = Task.Delay(1000);
//     await delay;
//     Console.WriteLine("等我一秒钟");
// }