图片到控制器后 图片怎么就能上传到服务器里面的文件夹？

通过什么方式？服务器又是通过什么方式接收到图片的？

#客户端请求图片时，怎么返回来的？

jquery 又是怎么发送图片的？服务器怎么接收的?

求解惑！！
详细！详细！最好有原理

采纳回答留下email发给你，其他人如果也需要，可以从 https://download.csdn.net/download/caozhy/11120832 下载

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using Q757140.Models;
using System.IO;

namespace Q757140.Controllers
{
    public class GalleryController : Controller
    {
        //
        // GET: /Gallery/

        public ActionResult Index()
        {
            //清除所有数据，可以用下面3行
            //var model = GalleryModel.Photos;
            //model.Clear();
            //model.SaveChanges();
            return View(GalleryModel.Photos);
        }

        //
        // GET: /Gallery/Create

        public ActionResult Create()
        {
            return View(new Photo()); //创建一个新图片
        }

        //
        // POST: /Gallery/Create
        [HttpPost]
        public ActionResult Create(FormCollection fc)
        {
            string description = fc["Description"].ToString(); //获得描述信息
            HttpPostedFileBase file = Request.Files["file_upload"]; //获得上传文件
            if (file != null)
            {
                var filename = Path.Combine(Request.MapPath("~/Upload"), file.FileName); //获得文件名
                file.SaveAs(filename); //保存文件到服务器
                var id = GalleryModel.Photos.InsertPhoto(filename, description); //保存到模型
                return RedirectToAction("Details", new { id }); //显示图片
            }
            return View();
        }

        //
        // GET: /Gallery/Details

        public ActionResult Details(int id)
        {
            return View(GalleryModel.Photos.Single(x => x.ID == id)); //显示模型
        }

        public FileResult Images(int id)
        {
            var path = GalleryModel.Photos.Single(x => x.ID == id).Path;
            return File(System.IO.File.ReadAllBytes(path), "image/jpeg"); //将服务器的图片返回客户端
        }

    }
}

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Q757140.Models.Photo>" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
    Details
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

    <h2>Details</h2>

    <fieldset>
        <legend>Fields</legend>

<%--        <div class="display-label">ID</div>
        <div class="display-field"><%: Model.ID %></div>

        <div class="display-label">Path</div>
        <div class="display-field"><%: Model.Path %></div>--%>

        <img src = "../Images/<%:Model.ID %>" alt = "" />

        <div class="display-label">Description</div>
        <div class="display-field"><%: Model.Description %></div>

    </fieldset>
    <p>
<%--        <%: Html.ActionLink("Edit", "Edit", new { /* id=Model.PrimaryKey */ }) %> |--%>
        <%: Html.ActionLink("Back to List", "Index") %>
    </p>

</asp:Content>

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Q757140.Models.Photo>" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
    Create
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

    <h2>Create</h2>

    <% using (Html.BeginForm("Create", "Gallery", FormMethod.Post, new { enctype = "multipart/form-data" }))
       {%>
        <%: Html.ValidationSummary(true) %>

        <fieldset>
            <legend>Fields</legend>

<%--            <div class="editor-label">
                <%: Html.LabelFor(model => model.ID) %>
            </div>
            <div class="editor-field">
                <%: Html.TextBoxFor(model => model.ID) %>
                <%: Html.ValidationMessageFor(model => model.ID) %>
            </div>--%>

<%--            <div class="editor-label">
                <%: Html.LabelFor(model => model.Path) %>
            </div>
            <div class="editor-field">
                <%: Html.TextBoxFor(model => model.Path) %>
                <%: Html.ValidationMessageFor(model => model.Path) %>
            </div>--%>

            <input type="file" id="file_upload" name="file_upload" />

            <div class="editor-label">
                <%: Html.LabelFor(model => model.Description) %>
            </div>
            <div class="editor-field">
                <%: Html.TextBoxFor(model => model.Description) %>
                <%: Html.ValidationMessageFor(model => model.Description) %>
            </div>

            <p>
                <input type="submit" value="Create" />
            </p>
        </fieldset>

    <% } %>

    <div>
        <%: Html.ActionLink("Back to List", "Index") %>
    </div>

</asp:Content>

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<IEnumerable<Q757140.Models.Photo>>" %>

<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
    Index
</asp:Content>

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

    <h2>Index</h2>

    <table>
        <tr>
            <th></th>
            <th>
                ID
            </th>
<%--            <th>
                Path
            </th>--%>
            <th>
                Description
            </th>
        </tr>

    <% foreach (var item in Model) { %>

        <tr>
            <td>
<%--                <%: Html.ActionLink("Edit", "Edit", new { /* id=item.PrimaryKey */ }) %> |--%>
                <%: Html.ActionLink("Details", "Details", new { id=item.ID })%> |
<%--                <%: Html.ActionLink("Delete", "Delete", new { /* id=item.PrimaryKey */ })%>--%>
            </td>
            <td>
                <%: item.ID %>
            </td>
<%--            <td>
                <%: item.Path %>
            </td>--%>
            <td>
                <%: item.Description %>
            </td>
        </tr>

    <% } %>

    </table>

    <p>
        <%: Html.ActionLink("Create New", "Create") %>
    </p>

</asp:Content>

上传到到src下面的目录里面去啊