ASP. Net core creates razor page and uploads multiple files (buffer mode) (Continued)

   Continue to learn the Microsoft upload file example , Learning support directory browsing 、 Delete file 、 Download files and other functions , And migrate it to the previously created webapp In the project .
   The above functions related to file operation mainly adopt PhysicalFileProvider Class implementation , This class is used to find files using the file system on the disk . In fact, it can also be used System.IO Namespace to get file information , But there is no PhysicalFileProvider Easy to use , And the latter can be called by other classes in the project in the form of registration service .
   By calling PhysicalFileProvider Class GetDirectoryContents Function to get the file and folder information under the specified directory , The list is transferred and displayed in the page by binding the model . Support directory browsing 、 Delete file 、 The background code for downloading files and other functions is as follows （ Code stripped from Microsoft sample programs ）

	public IDirectoryContents PhysicalFiles {
     get; private set; }

    public async Task OnGetAsync()
    {
    
        PhysicalFiles = _fileProvider.GetDirectoryContents(string.Empty);
    }
    
	public IActionResult OnGetDownloadPhysical(string fileName)
    {
    
        var downloadFile = _fileProvider.GetFileInfo(fileName);

        return PhysicalFile(downloadFile.PhysicalPath, MediaTypeNames.Application.Octet, fileName);
    }

     public IActionResult OnGetDeletehysical(string fileName)
     {
    
         if (string.IsNullOrEmpty(fileName))
         {
    
             return RedirectToPage("/Index");
         }

         IFileInfo RemoveFile = _fileProvider.GetFileInfo(fileName);

         if (RemoveFile.Exists)
         {
    
             System.IO.File.Delete(RemoveFile.PhysicalPath);
         }

         PhysicalFiles = _fileProvider.GetDirectoryContents(string.Empty);

         return Page();
     }

   The code in the front page is also a combination of different pages in Microsoft's example , This test can run normally .

<div>
<form enctype="multipart/form-data" method="post">
    <dl>
        <dt>
            <label asp-for="MultiFiles"></label>
        </dt>
        <dd>
            <input asp-for="MultiFiles" type="file" multiple accept=".pdf"/>
            <span asp-validation-for="MultiFiles"></span>
        </dd>
    </dl>
    <input asp-page-handler="Upload" class="btn" type="submit" value=" Upload files " />
</form>

<p class="result">
    @Model.Result
</p>
</div>
<div>
<h1>Files stored on disk</h1>

@if (Model.PhysicalFiles.Count() == 0)
{
    <p>
        No files are available. Visit one of the file upload scenario pages to upload one or more files.
    </p>
}
else
{
    <table>
        <thead>
            <tr>
                <th></th>
                <th>
                    Name
                </th>
                <th>
                    Size (bytes)
                </th>
                <th>
                    <code>PhysicalFileResult</code> from storage
                </th>
            </tr>
        </thead>
        <tbody>
            @foreach (var file in Model.PhysicalFiles) {
                <tr>
                    <td>
                        <a asp-page-handler="Deletehysical" asp-route-fileName="@file.Name">Delete</a>
                    </td>
                    <td>
                        <b>@file.Name</b><br>
                    </td>
                    <td class="text-center">
                        @file.Length.ToString("N0")
                    </td>
                    <td class="text-center">
                        <a asp-page-handler="DownloadPhysical" asp-route-fileName="@file.Name">Download</a>
                    </td>
                </tr>
            }
        </tbody>
    </table>
}
</div>

   Finally, the program running effect , As shown in the figure below ：

reference ：
[1]https://docs.microsoft.com/zh-cn/dotnet/api/microsoft.extensions.fileproviders.physicalfileprovider?view=dotnet-plat-ext-6.0
[2]https://docs.microsoft.com/zh-cn/aspnet/core/mvc/models/file-uploads?view=aspnetcore-6.0