c#实现内存映射文件共享内存----可读可写

例一：

1.写入文件-----创建的项目：控制台应用(.NET Framework)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using System.IO.MemoryMappedFiles;

namespace Shared_Memory1
{
    class Program
    {
        static void Main(string[] args)
        {
            long capacity = 1 << 10 << 10;

            //创建或者打开共享内存
            using (var mmf = MemoryMappedFile.CreateOrOpen("testMmf", capacity, MemoryMappedFileAccess.ReadWrite))
            {
                //通过MemoryMappedFile的CreateViewAccssor方法获得共享内存的访问器
                var viewAccessor = mmf.CreateViewAccessor(0, capacity);
                //循环写入，使在这个进程中可以向共享内存中写入不同的字符串值
                while (true)
                {
                    Console.WriteLine("请输入一行要写入共享内存的文字：");

                    string input = Console.ReadLine();
                    
                    //向共享内存开始位置写入字符串的长度
                    viewAccessor.Write(0, input.Length);

                    //向共享内存4位置写入字符
                    viewAccessor.WriteArray(4, input.ToArray(), 0, input.Length);
                }
            }
        }
    }
}

2.读取文件-----创建的项目：Windows 窗体应用(.NET Framework)

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.IO.MemoryMappedFiles;
using System.Threading;

namespace Shared_Memory2
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Button1_Click(object sender, EventArgs e)
        {
            long capacity = 88888;

            using (var mmf = MemoryMappedFile.OpenExisting("testMmf"))
            {
                MemoryMappedViewAccessor viewAccessor = mmf.CreateViewAccessor(0, capacity);

                //循环刷新共享内存字符串的值
                //while (true)
                //{
                    //读取字符长度
                    int strLength = viewAccessor.ReadInt32(0);
                    char[] charsInMMf = new char[strLength];
                    //读取字符
                    viewAccessor.ReadArray(4, charsInMMf, 0, strLength);                
                    textBox1.Text = new string(charsInMMf);
                    Thread.Sleep(200);
                //}
            }
        }
    }
}

例二

1.写入文件

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO.MemoryMappedFiles;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WriteRead
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        private void Button3_Click(object sender, EventArgs e)
        {
            MemoryMappedFile memory = MemoryMappedFile.CreateOrOpen("testMmf", 1024);  // 创建指定大小的内存文件，会在应用程序退出时自动释放
            MemoryMappedViewAccessor accessor1 = memory.CreateViewAccessor(0,1024);           // 访问内存文件对象        
            if(textBox1.Text=="")
            {
                MessageBox.Show("请输入值","经度", MessageBoxButtons.OK);
            }
            else
            {               
                Double value = Convert.ToDouble(textBox1.Text);
                accessor1.Write(4, value);   // 在指定位置写入double值
                /*
                TextBox[] txts = new TextBox[3]; //创建控件数组（文本框数组）
                txts[0] = this.textBox1;
                txts[1] = this.textBox2;
                txts[2] = this.textBox3;                
                double[] arr = new double[3]; //创建用于存储文本框中数据的数组arr[]               
                for (int i = 0; i <= 2; i++)  //将文本框数据传入数据数组arr[]中
                {
                    arr[i] = Convert.ToDouble(txts[i].Text);
                }
                accessor1.WriteArray(4, arr, 0, arr.Length);
                */
            }
            accessor1.Dispose();        // 释放资源
        }    
    }
}

2.读取文件

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.IO.MemoryMappedFiles;
using System.Threading;

namespace Shared_Memory3
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Button1_Click(object sender, EventArgs e)
        {            
            try
            {
                MemoryMappedFile memory = MemoryMappedFile.OpenExisting("testMmf");       // 获取指定名称内存文件
                MemoryMappedViewAccessor accessor1 = memory.CreateViewAccessor();           // 访问内存文件对象

                Double value = accessor1.ReadDouble(4); // 读取指定位置的数据
                textBox1.Text = Convert.ToString(value);                                   
               
                accessor1.Dispose();                
                Thread.Sleep(200);
            }

            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
        }
    }
}

 

参考：

https://blog.csdn.net/scimence/article/details/79417331
https://www.cnblogs.com/flyant/p/4443187.html
https://blog.csdn.net/changblade/article/details/82027440
http://c.biancheng.net/view/2928.html