Span复习

Span复习

using System;
 
namespace Span复习
{
    class Program
    {
        static void Main(string[] args)
        {
            //Console.WriteLine("Hello World!");
            //IntroSpans();
            //var span1 = IntroSpans();
 
            //CreatSlices(span1);
 
            int[] int1 = {,,,,,,,,,,};
            int[] int2 = {,,,,,,};
            var span1 = new Span<int>(int1);
            var span2 = new Span<int>(int2);
            ChangeValues(span1,span2);
        }
 
        //使用Span<T>，可以直接访问数组元素。数组的元素没有复制，但是它们可以直接使用，这比复制要快。
        private static Span<int> IntroSpans()
        {
            int[] arr1 = new int[] {,,,,,};
            var span1 = new Span<int>(arr1);
            span1[] = ;
            System.Console.WriteLine($"arr1[1] is changed via span[1]: {arr1[1]}");
            System.Console.WriteLine($"span1[1]: {span1[1]}");
            return span1;
 
        }
 
        //创建切片
        private static void CreatSlices(Span<int> span1)
        {
            System.Console.WriteLine(nameof(CreatSlices));
            int[] arr2 = {,,,,,,};
            //var span2 = new Span<int>(arr2);
            var span3 = new Span<int>(arr2,start:,length:);
            var span4 = span1.Slice(start:,length:);
 
            DisplaySpan("Content of span3:",span3);
            DisplaySpan("Content of span4:" ,span4);
            System.Console.WriteLine();
 
        }
 
        //DisplaySpan()用于显示Span的内容
        private static void DisplaySpan(string title,ReadOnlySpan<int> span)
        {
            System.Console.WriteLine(title);
            for(int i = ;i<span.Length;i++)
            {
                System.Console.Write($"{span[i]} ");
 
            }
            System.Console.WriteLine();
 
        }
 
        //使用Span改变值
        private static void ChangeValues(Span<int> span1,Span<int> span2)
        {
            System.Console.WriteLine(nameof(ChangeValues));
            var span4 = span1.Slice(start:);
            span4.Clear();//清除了span1从第5位开始后面的数，并用数0填充
            DisplaySpan("content of span1",span1);
            var span5 = span2.Slice(start:,length:);
            span5.Fill();//span2从第4位开始的三位，用数42来填充
            DisplaySpan("content of span2",span2);
            span5.CopyTo(span1);
            DisplaySpan("content of span1",span1);
            if(!span1.TryCopyTo(span4))
            {
                System.Console.WriteLine("Couldn't copy span1 to span4 because span4 is to small ");
                System.Console.WriteLine($"length of span1: {span1.Length},length of span4: {span4.Length} ");
 
            }
            System.Console.WriteLine();
 
        }
    }
}

使用Span改变值事例输出如下

ChangeValues
content of span1
 
content of span2
 
content of span1
 
Couldn't copy span1 to span4 because span4 is to small
length of span1: ,length of span4: