C#语言学习--基础部分(十六)数组(2)

五种数组Copy: ConsoleDemo

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ArrayDemo
{
class Program
{
static void Main(string[] args)
{
int[] pins;
pins = new int[4]{7,3,4,7};//两大特性:1.数组实例化完毕以后,定义下来数组元素的个数，数组元素的个数就不能改变.2.数组中每一个元素所存储的数值必须都是相同的数据类型.
//foreach (int s in pins)
//{
// Console.WriteLine(s);
//}
for(int x=0;x<pins.Length;x++)
{
Console.WriteLine(pins[x]);
}
Console.WriteLine(pins[0]);　//数组的访问
Console.WriteLine(pins[1]);
Console.WriteLine(pins[2]);
Console.WriteLine(pins[3]);
//pins = new int[3] { 7, 3, 4, 7 };//初始化长度不对应
//pins = new int[4] { 7, 3, 4 };　//初始化长度不对应
//int[] pins2;
//int i =int.Parse( Console.ReadLine());//动态指字数组维数
//pins2 = new int[i];
int[] pins3 = { 9, 3, 7, 2 }; //编译器会默认认为数组元素的个数为4
//隐式数组类型
var names = new[] { "aa", "bb" };
foreach (var name in names)
{
Console.WriteLine(name);
}
//var bad = new[] { "aa", "bb", 1, 2 };
var numbers = new[] { 11, 22, 33, 33.33, 45.35,23.9999999 };//double类型
Console.WriteLine(numbers[numbers.Length -1]);
//数组copy
int []pins4=new int[]{7,3,5,2};
int[] pins5;
//地址copy
pins5 = pins4; //此种赋值方式并不是把pins4数组里面每个元素都copy一份到pins5,这种赋值操作其实是把pins4这种整型数组的引用类型保存的地址copy到pins5中.
foreach (int pin in pins5)
{
Console.WriteLine(pin);
}
pins4[1] = 100;
Console.WriteLine(pins5[1]);
//copy一个全新的数组
int[] pins6 = new int[pins4.Length];
for(int j=0;j<pins4.Length;j++)
{
pins6[j]=pins4[j];
}
pins4[1] = 200;
Console.WriteLine(pins6[1]);
//eg2
string[] countrys = new string[] { "中国", "日本", "韩国", "朝鲜" };
string[] ctrycopy = new string[countrys.Length];
countrys.CopyTo(ctrycopy, 0);//index从第几个元素开始copy,而且是copy到ctrycopy中第index个位置
countrys[3] = "印度";
foreach (string ctry in countrys)
{
Console.WriteLine(ctry);
}
Console.WriteLine("----------CopyTo------------");
foreach (string cctry in ctrycopy)
{
Console.WriteLine(cctry);
}
Console.WriteLine("----------------------");
//eg3　Array.Copy
Array.Copy(countrys, ctrycopy, countrys.Length);
countrys[1] = "美国";
foreach (string ctry in countrys)
{
Console.WriteLine(ctry);
}
Console.WriteLine("----------Array.Copy-ctrycopy----------");
foreach (string cctry in ctrycopy)
{
Console.WriteLine(cctry);
}
//eg4
string[] cloneCountrys = (string[])countrys.Clone();
Console.WriteLine("-----------------Clone----------------------");
countrys[1] = "俄罗斯";
foreach (string ctry in countrys)
{
Console.WriteLine(ctry);
}
Console.WriteLine("---------------------------------------------");
foreach (string cctry in cloneCountrys)
{
Console.WriteLine(cctry);
}
}
}
}