详解C#中的字符串拼接@ $

    static void Main(string[] args)
    {
    //这样就很方便写读取的文件路径，也不需要什么转义字符了
     StreamReader sr = new StreamReader(@"C:\Users\WANGWI8\Desktop\testStreamRead.txt");
     string line;
     while( (line = sr.ReadLine()) != null )
     {
       Console.WriteLine(line);
     }
     }

static void Main(string[] args)
    {
      var name = Console.ReadLine();
      var date = DateTime.Now;
      var result = $"hello {name} , you are my father , i am your son , writed at {date}";
      Console.WriteLine(result);
      var item2 =
      (
        name: "william",
        sex: 'f'
      );
      Console.WriteLine($"this is item : item.name : {item2.name} , this is sex : {item2.sex}");
      var inventory = new Dictionary<string, int>()
      {
        ["hammer, ball pein"] = 18,
        ["hammer, cross pein"] = 5,
        ["screwdriver, Phillips #2"] = 14
      };
      Console.WriteLine($"inventory on {DateTime.Now:d}");
      Console.WriteLine(" ");
      //负号的意思是左对齐，一共占据25个字符的空间
      Console.WriteLine($"|{"item",-25}|{"quantity",10}|");
      foreach (var item in inventory)
        Console.WriteLine($"|{item.Key,-25}|{item.Value,10}|");
    }