ｃ＃演算式：【X?.x】.cs の用例

ｃ＃演算式：【X?.x】.cs　の用例

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class SampleModel
    {
        public string id { get; set; }
    }
    public class Program
    {
        public static void Main(string[] args)
        {
            SampleModel sampleModel = null;
            Console.WriteLine("|" + sampleModel?.id + "|");
            try{
                if (string.IsNullOrWhiteSpace(sampleModel?.id))
                {
                    Console.WriteLine("1111");
                }
            } catch(Exception ex){
                    Console.WriteLine(ex);
            }
        }
    }
}

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