C#学习笔记- 浅谈数组复制,排序,取段,元组_C#

C#学习笔记- 浅谈数组复制,排序,取段,元组

2021-12-03 15:32C#教程网 C#

下面小编就为大家带来一篇C#学习笔记- 浅谈数组复制,排序,取段,元组。小编觉得挺不错的，现在就分享给大家，也给大家做个参考。一起跟随小编过来看看吧

C#学习笔记- 浅谈数组复制,排序,取段,元组

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using System;
using System.Collections.Generic;
 
namespace Application
{
class Test
{
static void Main ()
{
 
//元组类型Tuple是静态类型，用静态方法创建实例，超过8个元素则第8个元素是元组类型
 
var tupe = Tuple.Create<int,int,string,string> (1, 2, "a", "b");
Console.WriteLine ("{ 0},{ 1}",tupe.Item1, tupe.Item3);
 
 
//=====Array类是抽象类，只能通过它的静态方法CreateInstance()创建实例
 
//=====如果事先不知道类型，可以用此方法
 
Array arrays = Array.CreateInstance (typeof(int), 5);
for (int i = 0; i < arrays.Length; i++) {
arrays.SetValue (35, i);
Console.WriteLine (arrays.GetValue (i));
}
 
 
Person[] persons = {
new Person { firstName = "su", lastName = "uifu" },
new Person { firstName = "chen", lastName = "xaohua" },
new Person { firstName = "cbb", lastName = "ruifu" },
new Person { firstName = "utt", lastName = "xiaohua" }
} ;
 
//=====Clone()复制数组，引用类型复制索引值，值类型复制值
 
Person[] persons1 = persons.Clone ();
Array.Sort (persons, new PersonComparer (PersonCompareType.lastName));
foreach (var p in persons) {
Console.WriteLine (p);
}
 
//＝＝＝＝＝＝ArraySegment<T>对数组取段＝＝＝＝
var segments = new ArraySegment<Person> (persons, 1, 2);
for (int i = segments.Offset; i < segments.Offset + segments.Count; i++) {
Console.WriteLine (segments.Array [i]);
}
}
 
public class Person
{
public string firstName{ get; set; }
public string lastName{ get; set; }
 
public override string ToString ()
{
return String.Format ("{ 0},{ 1}", firstName, lastName);
}
}
//＝＝＝＝＝＝要对引用类型的数组使用Array.sort()方法，必须对类实现IComparable<T>接口
 
//＝＝＝＝＝＝或写一个附加类并实现Comparer<T>接口
public enum PersonCompareType
{
firstName,
lastName
}
 
public class PersonComparer:IComparer<Person>
{
private PersonCompareType pct;
 
public PersonComparer (PersonCompareType pct)
{
this.pct = pct;
}
public int Compare(Person x,Person y)
{
if (x == null)
throw new ArgumentNullException ();
if (y == null)
throw new ArgumentNullException ();
switch (pct) {
case PersonCompareType.firstName:
return x.firstName.CompareTo (y.lastName);
case PersonCompareType.lastName:
return x.lastName.CompareTo (y.lastName);
default:
throw new ArgumentException ("no..");
}
}
 
}
}