c# 文件上传下载

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原创最新推荐文章于 2026-02-25 23:21:41 发布 1.3k 阅读 AI 写同款· GEO 优化 ›

C#实现文件上传下载工具类本篇文章在VS2013环境下采用C#语言实现将文件上传和下载功能。上传时，为避免文件名在服务器中重复，采用“服务器时间+8位随机码+文件名+文件后缀“的方式作为服务器上的文件名；下载采用的是WebAPI的方式进行的，下载成功后可自定义文件的保存路径。具体源码如下所示：using System; using System.IO; using System.Net; using System.Net.H 阅读详情

1. 介绍

C#文件上传下载用WebClient类实现

微软官方使用Demo

https://docs.microsoft.com/en-us/dotnet/api/system.net.webclient.downloadfile?view=netframework-4.7.2

架构为B/S

模板

服务器: WebForm

客户端:ConsoleApplication

2. 代码

2.1 客户端

解决方案:

WebClientOper.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;

namespace WebClientOperation
{
    class WebClientOper
    {
        public bool UploadFile(string address, string fileName)
        {
            if (!File.Exists(fileName))
                return false;

            using (WebClient client = new WebClient())
            {
                client.UploadProgressChanged += Client_UploadProgressChanged; ;
                client.UploadFileCompleted += Client_UploadFileCompleted; ;
                client.UploadFileAsync(new Uri(address), fileName);

                Console.ReadKey();
            }

            return true;
        }

        private void Client_UploadFileCompleted(object sender, UploadFileCompletedEventArgs e)
        {
            Console.WriteLine("Upload Completed...");
        }

        private void Client_UploadProgressChanged(object sender, UploadProgressChangedEventArgs e)
        {
            Console.WriteLine($"{e.ProgressPercentage}:{e.BytesReceived}/{e.TotalBytesToReceive}");
        }

        public bool DownloadFile(string address, string fileName)
        {
            using (WebClient client = new WebClient())
            {
                client.DownloadProgressChanged += Client_DownloadProgressChanged; ;
                client.DownloadFileCompleted += Client_DownloadFileCompleted;
                client.DownloadFileAsync(new Uri(address), fileName);

                Console.ReadKey();
            }

            return true;
        }

        private void Client_DownloadFileCompleted(object sender, AsyncCompletedEventArgs e)
        {
            Console.WriteLine("Download Completed...");
        }

        private void Client_DownloadProgressChanged(object sender, DownloadProgressChangedEventArgs e)
        {
            Console.WriteLine($"{e.ProgressPercentage}:{e.BytesReceived}/{e.TotalBytesToReceive}");
        }

        public void DisplayImage()
        {

        }
    }
}

Program.cs

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

namespace WebClientOperation
{
    class Program
    {
        static void Main(string[] args)
        {
            Test();
        }

        static void Test()
        {
            string filePath = @"E:\sky.jpg";


            // IIS Upload
            // string address = @"http://localhost:22903/WebServer.aspx";
            // IIS Download 
            // pic path = "C:\Users\Irvin\source\repos\WebServer\WebServer\sky.jpg"
            string address = @"http://localhost:22903/WebServer.aspx/sky.jpg";

            WebClientOper webClientOper = new WebClientOper();
            // webClientOper.UploadFile(address, filePath);
            webClientOper.DownloadFile(address, filePath);
        }
    }
}

2.2 服务器:

创建空web项目

添加网站WebServer

解决方案

WebServer.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="WebServer.aspx.cs" Inherits="WebServer" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
        <div>
        </div>
    </form>
</body>
</html>

WebServer.aspx.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class WebServer : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        foreach (string f in Request.Files.AllKeys)
        {
            HttpPostedFile file = Request.Files[f];
            file.SaveAs("E:\\UploadedFiles\\" + file.FileName);
        }
    }
}

3. 测试

3.1 上传测试

修改上传URL为服务器主页URL, 启动服务器,拷贝并修改address