C#中使用where子句限制泛型方法的泛型类型

http://mgc.ahau.edu.cn/article.asp?id=616

C#中使用where子句限制泛型方法的泛型类型。
1.要求泛型类型实现一个接口或派生于某个基类；
2.不能定义必须由泛型类型实现的运算符。

TestMethodTTwo.cs:

using System; using System.Collections.Generic; namespace Magci.Test.Collections { //定义接口 public interface IAccount { string Name { get; } decimal Balance { get; } } public class Account : IAccount { private string name; public string Name { get { return name; } } private decimal balance; public decimal Balance { get { return balance; } } public Account(string name, decimal balance) { this.name = name; this.balance = balance; } } public class Algorithm { //声明泛型方法 public static decimal Total(IEnumerable e) //使用where子句限制泛型类型 where TAccount : IAccount { decimal total = 0; foreach (TAccount a in e) { total += a.Balance; } return total; } } public class TestMethodTTwo { public static void Main() { List accounts = new List(); accounts.Add(new Account("Magci", 9999.99m)); accounts.Add(new Account("Haha", 1241.33m)); accounts.Add(new Account("Heihei", 1551.2m)); accounts.Add(new Account("Kevin", 2643m)); //调用泛型方法 decimal total = Algorithm.Total(accounts); Console.WriteLine("Total : {0:C}", total); } } }