DotNetCore Mvc文件上传功能

FileUploadController 代码，使用了IFormFile，并且把文件保存到本地。

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.ViewFeatures;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Web.Filters;

namespace Web.Controllers
{
    [ApiException]
    [Route("api/fileUpload")]
    public class FileUploadController : Controller
    {
        public IActionResult Index()
        {
            return View();
        }

        [HttpPost("UploadFile")]
        public async Task<ActionResult> UploadFile(IFormFile photo)
        {
            if (photo == null || photo.Length == 0)
                return Content("No file selected for upload.");

            var fileFolder = Path.Combine("", "wwwroot/static/back.png");

            using (var stream = new FileStream(fileFolder, FileMode.Create))
            {
                await photo.CopyToAsync(stream);
            }

            return Ok();
        }
    }
}

前端HTML代码可以直接copy到cshtml文件中使用，逻辑也比较容易理解：

<div id="form-background" style="padding:10px 10px 10px 10px;">

<h4>请选择需要上传的图片：</h4>    
<hr />
<div class="row">
    <form id="uploadform" name="uploadform" enctype="multipart/form-data" method="post">
        <div class="form-group">
            <input type="file" name="photo" id="photo" value="" placeholder="首页背景图片">
            <br />
            <input type="button" class="form-control" onclick="postData();" value="上传" name="" style="100px;height:30px;">
        </div>
    </form>
</div>
</div>

脚本使用了JQuery

    <script type="text/javascript">
        function postData() {

            var formData = new FormData();
            formData.append("photo", $("#photo")[0].files[0]);

            $.ajax({
                url: '/api/fileupload/uploadFile',
                type: 'POST',
                data: formData,
                contentType: false,
                processData: false,
                success: function (res) {
                    console.log(res);
                    alert("上传成功！");
                },
                error: function () {
                    alert("上传失败！");
                }
            })
        }
    </script>

值得注意的是，前端代码中的文件名photo需要和后端一致

//前端
formData.append("photo", $("#photo")[0].files[0]);
//后端
public async Task<ActionResult> UploadFile(IFormFile photo)

以上实现的是单文件上传的功能.