集合-列表
.net framework为动态列表提供了泛型类List<T>.继承了6个接口，其定义如下：
public class List<T> : IList<T>, ICollection<T>, IEnumerable<T>, IList, ICollection, IEnumerable
List<int> list = new List<int>(8); //创建列表
Console.WriteLine(list.Count.ToString());//列表元素数量
Console.WriteLine(list.Capacity.ToString());//列表容量
list.TrimExcess();// 去除不需要的容量，当数量达到容量90%时，不处理。
var liststrs = new List<string> { "bj", "sh" };//可定义时初始化值
liststrs.Add("wuhan");//Add添加元素
liststrs.Insert(1, "tj");//Insert插入元素
liststrs.ForEach(Console.WriteLine);//此方法相当于foreach循环
liststrs.RemoveAt(0);//移除
Console.WriteLine(liststrs[0]);//通过下标访问元素
具体例子代码：
namespace ConsoleApplication1
{
public class Racer : IFormattable, IComparable<Racer>
{
public int ID { get; private set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string Country { get; set; }
public int Winns { get; set; }
public Racer(int id, string firstname, string lastname, string country = null, int winns = 0)
{
this.ID = id;
this.FirstName = firstname;
this.LastName = lastname;
this.Country = country;
this.Winns = winns;
}
public override string ToString()
{
return string.Format("{0}-{1}", FirstName, LastName);
}
public string ToString(string format, IFormatProvider formProvider)
{
if (format == null)
{
format = "N";
}
switch (format.ToUpper())
{
case "N":
return ToString();
case "F":
return FirstName;
case "L":
return LastName;
case "W":
return string.Format("{0},win:{1}", ToString(), Winns);
case "C":
return string.Format("{0},country:{1}", ToString(), Country);
case "A":
return string.Format("{0},win:{1},country:{2}", ToString(), Winns, Country);
default:
throw new FormatException(string.Format(formProvider, "字母{0}未定义", format));
}
}
public string Tostring(string format)
{
return ToString(format, null);
}
public int CompareTo(Racer other)
{
int compare = this.LastName.CompareTo(other.LastName);
if (compare == 0)
{
compare = this.FirstName.CompareTo(other.FirstName);
}
return compare;
}
}
public class RacerCompare : IComparer<Racer>
{
public enum RacerType
{
firstname,
lastname,
country,
winns
}
private RacerType racerType;
public RacerCompare(RacerType racertype)
{
this.racerType = racertype;
}
public int Compare(Racer x, Racer y)
{
if (x == null)
{
throw new ArgumentNullException("x");
}
if (y == null)
{
throw new ArgumentNullException("y");
}
int result;
switch (racerType)
{
case RacerType.firstname:
result = x.FirstName.CompareTo(y.FirstName);
break;
case RacerType.lastname:
result = x.LastName.CompareTo(y.LastName);
break;
case RacerType.country:
result = x.Country.CompareTo(y.Country);
break;
case RacerType.winns:
result = x.Winns.CompareTo(y.Winns);
break;
default:
throw new ArgumentException("未定义的类型");
}
return result;
}
}
public class Person
{
private string name;
public Person(String name)
{
this.name = name;
}
public override string ToString()
{
return name;
}
}
class Program
{
static void Main(string[] args)
{
Racer zhang = new Racer(1, "zhang", "gong", "shangxiu", 0);
Racer xi = new Racer(2, "xi", "feng", "china", 3);
Racer mao = new Racer(3, "mao", "tai", "zhongguo", 6);
List<Racer> recers = new List<Racer>(10) { zhang, xi, mao };
recers.Add(new Racer(7, "wu", "liangye", "tangchao", 9));
recers.AddRange(new Racer[] {
new Racer(9, "du", "kang", "hanchao", 12),
new Racer(10,"qing","shui","zhonghua",100)});
recers.Sort(new RacerCompare(RacerCompare.RacerType.lastname));
recers.ForEach(Console.WriteLine);
List<Person> persons = recers.ConvertAll<Person>(p => new Person(p.FirstName + " " + p.LastName));
persons.ForEach(Console.WriteLine);
Console.Read();
}
}
}
