C# Conditional的使用

#define ABC // 定义了 ABC 则 会输出,否则,不输出

using System;
using System.Diagnostics;

namespace CSharpTutorials
{
    public class Trace
    {
        [Conditional("ABC")]
        public static void Message(string traceMessage)
        {
            Console.WriteLine("[TRACE] - " + traceMessage);
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Trace.Message("Hello");
        }
    }
}