OneNote2PDF/OneNote2PDF/App.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace OneNote2PDF
{
    /// <summary>
    /// 全局 app 对象
    /// </summary>
    class App
    {
        public string inputDir = "";
        public string outputDir = "";

        private static App app;
        private static readonly object locker = new object(); // 对象锁标志

        public static App getInstance()
        {
            if (app == null)
            {
                lock (locker) //标志对象加锁，多线程内部代码会挂起
                {
                    if (app == null)
                    {
                        app = new App();
                    }
                }
            }
            return app;
        }
    }
}