在C#13中，对params的定义类型进行了扩充，不仅仅是数组了，开始支持集合了。IEnumerable<T>，IList<T>，List<T>，Span<T>，ReadOnlySpan<T>都得到了支持。这亲就不用每次进行一次转换工作了。实例如下：
F0(1, 2, 3, 4);F1(1, 2, 3, 4);F2(1, 2, 3, 4);F3(1, 2, 3, 4);F4(1, 2, 3, 4);F5(1, 2, 3, 4);static void F0(params int[] arr){foreach (var item in arr){Console.WriteLine(item);}}static void F1(params List<int> list){foreach (var item in list){Console.WriteLine(item);}}static void F2(params IList<int> list){foreach (var item in list){Console.WriteLine(item);}}static void F3(params IEnumerable<int> list){foreach (var item in list){Console.WriteLine(item);}}static void F4(params Span<int> list){foreach (var item in list){Console.WriteLine(item);}}static void F5(params ReadOnlySpan<int> list){foreach (var item in list){Console.WriteLine(item);}}
另一个是对正则的源生成器进行了扩展，不仅仅是方法，这次加上了属性，我个人感觉属性是更优雅的做法，毕竟正则一般是约束数据格式的，与属性的匹配度要高一些。
var email = new EmailDemo();email.SendEmail("abc@aaa");email.EMail = "abc@gmail.com";public partial class EmailDemo{[]private static partial Regex ValidEMail();public void SendEmail(string email){if (!ValidEMail().IsMatch(email)){Console.WriteLine("emal不正确");return;}Console.WriteLine("发送EMail");}[]private static partial Regex ValidateEMail { get; }private string _email;public string EMail{get{return _email;}set{if (ValidateEMail.IsMatch(value)){_email = value;}else{Console.WriteLine("emal不正确");}}}}
