C# 下载文件

方法一：

[HttpGet]
        [EnableCors("userLogin")]
        public IActionResult DownloadFile(string url , string token)
        {
            var filePath = "D://xzc/" + _Configuration.GetSection("module").Value + "/Uploads/" + url;
            string[] tmpArr = url.Split("_");
            var fileName = tmpArr.AsQueryable().Last(); ;
            FileStream fs = new FileStream( filePath, FileMode.OpenOrCreate);
            fs.Close();
            return File(new FileStream(filePath, FileMode.Open), "application/octet-stream", fileName);
        }

方法二：

strFileName这个是下载下来的文件显示的名称，strToPath + targetFileName 这个是文件所在路径及其物理文件名（一般是字母加数字组合起来的）
调用：WebFile.downloadByStream(Response, strFileName, strToPath + targetFileName);

public static void downloadByStream(HttpResponse Response, string fileName, string filePath) 
{ 
    if (File.Exists(filePath)) 
    { 
        //以字符流的形式下载文件 
        FileStream fs = new FileStream(filePath, FileMode.Open); 
        byte[] bytes = new byte[(int)fs.Length]; 
        fs.Read(bytes, 0, bytes.Length); 
        fs.Close(); 
        Response.ContentType = "application/octet-stream"; 
        //通知浏览器下载文件而不是打开 
        Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8)); 
        Response.BinaryWrite(bytes); 
        Response.Flush(); 
        Response.End(); 
    } 
}                                                