C#2和3之间的差异

Question

我对C#或.net知之甚少,但我有兴趣了解它们.

引起我兴趣的一件事是我一直听说"C#3真的很棒".
这是为什么？与C#2的区别是什么？差异仅在C#或.net中吗？

提前致谢.

Answer 1

我有一篇关于此的文章:Bluffer的C#3指南.显然,我的书中有更多细节,但它应该足以让你前进.简而言之:

• 自动实现的属性:

  public int Value { get; set; }
  

• 对象和集合初始值设定项:

  Form form = new Form { Size = new Size(100, 100),
                         Controls = { new Label { Text = "Hi" } }
                       };
  List<string> strings = new List<string> { "Hi", "There" };
  

• 隐式输入的局部变量:

  var x = new Dictionary<string, int>(); // x is still statically typed
  

• 隐式类型数组:

  DoSomething(new[] { "hi", "there"}); // Creates a string array
  

• 匿名类型:

  var jon = new { Name = "Jon", Age = 33 };
  

• Lambda表达式(比如匿名方法但更短):

  Func<string, int> lengthFunc = x => x.Length;
  

• 表达树:

  // Representation of logic as data
  Expression<Func<string, int>> lengthExpression = x => x.Length;
  

• 扩展方法:(静态方法,就像第一个参数类型的实例方法一样)

  public static string Reverse(this string text)
  {
      char[] chars = text.ToCharArray();
      Array.Reverse(chars);
      return new string(chars);
  }
  
  ...
  
  string hello = "olleh".Reverse();
  

• 查询表达式:

  var query = from person in people
              where person.Age > 18
              select person.Name;