c#客户端文件上传不存数据库也不想写http服务器的共享实现方法

使用window自带共享实现
创建共享文件夹
net share SharedFolder=D:\SharedFolder /GRANT:everyone,full
只读
net share SharedFolder=D:\SharedFolder /GRANT:everyone,read
net share查看共享

指定用户名和密码访问

默认情况下，局域网访问会走 Windows 登录账号。
如果你想指定用户名密码，需要在共享电脑上创建局域网用户：

net user user123 123456 /add
net localgroup "Users" user123 /add

手动映射为本地盘（系统层面）
net use Z: \\192.168.1.10\shared 123456 /user:user123

映射盘符后，读取、写入、删除共享文件夹完全像操作本地磁盘一样，不需要特殊 API。

using System;
using System.IO;
using System.Runtime.InteropServices;

public static class NetworkShareHelper
{
    [DllImport("mpr.dll")]
    private static extern int WNetAddConnection2(ref NETRESOURCE netResource, string password, string username, int flags);

    [DllImport("mpr.dll")]
    private static extern int WNetCancelConnection2(string name, int flags, bool force);

    [StructLayout(LayoutKind.Sequential)]
    private struct NETRESOURCE
    {
        public int dwScope;
        public int dwType;
        public int dwDisplayType;
        public int dwUsage;
        public string lpLocalName;
        public string lpRemoteName;
        public string lpComment;
        public string lpProvider;
    }

    private static void Connect(string networkFolder, string username, string password)
    {
        var netResource = new NETRESOURCE
        {
            dwType = 1, // RESOURCETYPE_DISK
            lpRemoteName = networkFolder
        };

        int result = WNetAddConnection2(ref netResource, password, username, 0);
        if (result != 0)
            throw new IOException($"无法连接共享文件夹（{networkFolder}），错误码：{result}");
    }

    private static void Disconnect(string networkFolder)
    {
        WNetCancelConnection2(networkFolder, 0, true);
    }

    /// <summary>
    /// 上传本地文件到共享目录（支持任意资源文件）
    /// </summary>
    public static void UploadFile(string localFilePath, string networkDestPath, string username = null, string password = null)
    {
        string folder = Path.GetDirectoryName(networkDestPath);
        try
        {
            if (!string.IsNullOrEmpty(username))
                Connect(folder, username, password);

            // 创建目标目录（若不存在）
            Directory.CreateDirectory(folder);

            File.Copy(localFilePath, networkDestPath, true);
            Console.WriteLine($"文件上传成功：{Path.GetFileName(localFilePath)} → {networkDestPath}");
        }
        finally
        {
            if (!string.IsNullOrEmpty(username))
                Disconnect(folder);
        }
    }

    /// <summary>
    /// 下载文件到本地
    /// </summary>
    public static void DownloadFile(string networkPath, string localDestPath, string username = null, string password = null)
    {
        string folder = Path.GetDirectoryName(networkPath);
        try
        {
            if (!string.IsNullOrEmpty(username))
                Connect(folder, username, password);

            if (!File.Exists(networkPath))
                throw new FileNotFoundException("共享文件不存在：" + networkPath);

            File.Copy(networkPath, localDestPath, true);
            Console.WriteLine($"下载成功：{networkPath} → {localDestPath}");
        }
        finally
        {
            if (!string.IsNullOrEmpty(username))
                Disconnect(folder);
        }
    }

    /// <summary>
    /// 删除共享文件
    /// </summary>
    public static void DeleteFile(string networkPath, string username = null, string password = null)
    {
        string folder = Path.GetDirectoryName(networkPath);
        try
        {
            if (!string.IsNullOrEmpty(username))
                Connect(folder, username, password);

            if (File.Exists(networkPath))
            {
                File.Delete(networkPath);
                Console.WriteLine("文件已删除：" + networkPath);
            }
            else
            {
                Console.WriteLine("文件不存在：" + networkPath);
            }
        }
        finally
        {
            if (!string.IsNullOrEmpty(username))
                Disconnect(folder);
        }
    }
}

使用

class Program
{
    static void Main()
    {
        string username = "user";
        string password = "123456";

        // 本地文件
        string localFile = @"D:\images\car.jpg";

        // 共享路径（目标）
        string networkFile = @"\\192.168.1.10\shared\car.jpg";

        try
        {
            // 上传资源文件
            NetworkShareHelper.UploadFile(localFile, networkFile, username, password);

            // 下载回来验证
            NetworkShareHelper.DownloadFile(networkFile, @"D:\downloaded\car_copy.jpg", username, password);

            // 删除共享文件
            // NetworkShareHelper.DeleteFile(networkFile, username, password);
        }
        catch (Exception ex)
        {
            Console.WriteLine("操作失败：" + ex.Message);
        }
    }
}