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//1、不支持nameof(List<>)Console.WriteLine(nameof(List<>));Console.WriteLine(nameof(List<string>));Console.WriteLine(nameof(List<int>));
//2、您可以向 lambda 表达式参数添加参数修饰符，例如scoped、ref、in、out或 ，ref readonly而无需指定参数类型：TryParse<int> parse1 = (text, out result) => Int32.TryParse(text, out result);//之前写法TryParse<int> parse2 = (string text, out int result) => Int32.TryParse(text, out result);
//3、 空条件赋值void SetPersonName(Person? person, string name){ //空条件赋值 person?.Name = name;}//4、属性支持fielddelegate bool TryParse<T>(string text, out T result);public partial class Person{ public string Name { get; set { if (string.IsOrEmpty(value)) { throw new Exception("Name cannot be or empty"); } field = value; } } public int Age { get; set { if (150 >= field && field >= 0) { field = value; } else { throw new Exception("Invalid age"); } } } //5、事件可以声明为部分成员 public partial event EventHandler? NameChanged; public partial Person();}
public partial class Person{ //5、实例构造函数可声明为部分成员  public partial Person() { Name = "Default Name"; Age = 0; }
 private EventHandler _nameChangedHandlers; // 实现声明：必须包含 add 和 remove public partial event EventHandler NameChanged { add { Console.WriteLine("Handler added."); _nameChangedHandlers += value; } remove { Console.WriteLine("Handler removed."); _nameChangedHandlers -= value; } } public void OnNameChanged() { _nameChangedHandlers?.Invoke(this, EventArgs.Empty); }}