上传图片asp.net Core

Question

我是 ASP.net COre 的新手，我想上传一个文件（一个图像）并将其存储在一个特定的文件夹中。 我一直在关注这个教程（ ASP.NET Core 中的文件上传），但我不知道如何将它存储在刚刚上传到服务器上的文件中，这是 html：

<form method="post" enctype="multipart/form-data" asp-controller="UploadFiles" asp-action="Index">
<div class="form-group">
    <div class="col-md-10">
        <p>Upload one or more files using this form:</p>
        <input type="file" name="files" multiple />
    </div>
</div>
<div class="form-group">
    <div class="col-md-10">
        <input type="submit" value="Upload" />
    </div>
</div>

这是控制器

[HttpPost("UploadFiles")]
public async Task<IActionResult> Post(List<IFormFile> files)
{
long size = files.Sum(f => f.Length);

// full path to file in temp location
var filePath = Path.GetTempFileName();

foreach (var formFile in files)
{
    if (formFile.Length > 0)
    {
        using (var stream = new FileStream(filePath, FileMode.Create))
        {
            await formFile.CopyToAsync(stream);
        }
    }
}

// process uploaded files
// Don't rely on or trust the FileName property without validation.

return Ok(new { count = files.Count, size, filePath});
}

这是我正在使用的课程

public interface IFormFile
{
string ContentType { get; }
string ContentDisposition { get; }
IHeaderDictionary Headers { get; }
long Length { get; }
string Name { get; }
string FileName { get; }
Stream OpenReadStream();
void CopyTo(Stream target);
Task CopyToAsync(Stream target, CancellationToken cancellationToken = null);
}

我只需要将图像存储在一个文件夹中，例如：C:\\Users\\DESKTOP-1603\\Desktop\\GestionSyndic\\GestionSyndic\\src\\WebApplication1\\wwwroot\\images\\ 并更改图像的名称，谢谢：D

Answer 1

简单步骤在 ASP.NET Core MVC 中上传文件

1.Demo.cshtml 查看代码片段

<form method="post" enctype="multipart/form-data" asp-controller="Demo" asp-action="Index">
<div class="form-group">
    <div class="col-md-10">
        <p>Upload one or more files using this form:</p>
        <input type="file" name="files" multiple />
    </div>
</div>
<div class="form-group">
    <div class="col-md-10">
        <input type="submit" value="Upload" />
    </div>
</div>

2. 演示控制器

为了展示演示，我创建了一个演示控制器，其中有 2 个操作方法，一个用于处理获取请求，另一个用于处理发布请求。

using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc;
using System;
using System.IO;
using System.Net.Http.Headers;

namespace WebApplication6.Controllers
{
    public class DemoController : Controller
    {
        private readonly IHostingEnvironment _environment;

        // Constructor
        public DemoController(IHostingEnvironment IHostingEnvironment)
        {
            _environment = IHostingEnvironment;
        }

        [HttpGet]
        public IActionResult Index()
        {
            return View();
        }

        [HttpPost]
        public IActionResult Index(string name)
        {
            var newFileName = string.Empty;

            if (HttpContext.Request.Form.Files != null)
            {
                var fileName = string.Empty;
                string PathDB = string.Empty;

                var files = HttpContext.Request.Form.Files;

                foreach (var file in files)
                {
                    if (file.Length > 0)
                    {
                        //Getting FileName
                        fileName = ContentDispositionHeaderValue.Parse(file.ContentDisposition).FileName.Trim('"');

                        //Assigning Unique Filename (Guid)
                        var myUniqueFileName = Convert.ToString(Guid.NewGuid());

                        //Getting file Extension
                        var FileExtension = Path.GetExtension(fileName);

                        // concating  FileName + FileExtension
                        newFileName = myUniqueFileName + FileExtension;

                        // Combines two strings into a path.
                        fileName = Path.Combine(_environment.WebRootPath, "demoImages") + $@"\{newFileName}";

                        // if you want to store path of folder in database
                        PathDB = "demoImages/" + newFileName;

                        using (FileStream fs = System.IO.File.Create(fileName))
                        {
                            file.CopyTo(fs);
                            fs.Flush();
                        }
                    }
                }


            }
            return View();
        }
    }
}

调试时的快照

存储图像的文件夹位置

Answer 2

您应该注入IHostingEnvironment以便您可以获得 Web 根目录（默认为wwwroot ）位置。

public class HomeController : Controller
{
    private readonly IHostingEnvironment hostingEnvironment;
    public HomeController(IHostingEnvironment environment)
    {
        hostingEnvironment = environment;
    }
    [HttpPost]
    public async Task<IActionResult> UploadFiles(List<IFormFile> files)
    {
        long size = files.Sum(f => f.Length);

        // full path to file in temp location
        var filePath = Path.GetTempFileName();

        foreach (var formFile in files)
        {
            var uploads = Path.Combine(hostingEnvironment.WebRootPath, "images");
            var fullPath = Path.Combine(uploads, GetUniqueFileName(formFile.FileName));
            formFile.CopyTo(new FileStream(fullPath, FileMode.Create));

        }
        return Ok(new { count = files.Count, size, filePath });
    }
    private string GetUniqueFileName(string fileName)
    {
        fileName = Path.GetFileName(fileName);
        return  Path.GetFileNameWithoutExtension(fileName)
                  + "_" 
                  + Guid.NewGuid().ToString().Substring(0, 4) 
                  + Path.GetExtension(fileName);
    }
}

这会将文件保存到wwwroot的images目录。

确保您的表单标签的action属性设置为 HomeController( /Home/UploadFiles ) 的UploadFiles操作方法

<form method="post" enctype="multipart/form-data" asp-controller="Home"
                                                  asp-action="UploadFiles">
    <div class="form-group">
        <div class="col-md-10">
            <p>Upload one or more files using this form:</p>
            <input type="file" name="files" multiple />
        </div>
    </div>
    <div class="form-group">
        <div class="col-md-10">
            <input type="submit" value="Upload" />
        </div>
    </div>
</form>

我不太确定你为什么要从这个返回 Ok 结果。 您可能会将重定向结果返回到列表页面。

Answer 3

刚刚使用了@Saineshwar 接受的答案，但做了一点重构作为一种扩展方法，以便于使用 IFromFile

public static string MakeFileUniqueName(this IFormFile formFile)
    {
        if (formFile.Length > 0)
        {
            string fileName =
                ContentDispositionHeaderValue.Parse(formFile.ContentDisposition).FileName.Trim('"');

            // concatinating  FileName + FileExtension
            return Guid.NewGuid() + Path.GetExtension(fileName);      
        }

        return string.Empty;
    }