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FileManager in Razor Pages

Updated on Dec 10, 2025

This article describes how to seamlessly integrate and configure the Telerik UI FileManager for ASP.NET Core in Razor Pages applications.

Referencing Handler Methods in Razor Pages

Razor Pages is an alternative to the MVC pattern that makes page-focused coding easier and more productive. This approach consists of a cshtml file and a cshtml.cs file (by convention, the two files have the same name).

The cshtml.cs file, known as the PageModel, contains handler methods that respond to HTTP requests. These methods are prefixed with On followed by the HTTP verb (for example, OnGet, OnPost, OnPostRead, OnPostCreate).

Handler methods declared in a PageModel can be referenced from any Razor Page using one of the following URL patterns:

  • Using Url.Page()

    C#
    Url.Page("PageName", "HandlerName")
    // OR
    Url.Page("/FolderName/PageName", "HandlerName")

    For example, Url.Page("Index", "Read") references the OnPostRead or OnGetRead handler method in the Index.cshtml.cs file.

  • Using a query string

    C#
    Url("/PathToPage?handler=HandlerName")

    For example, Url("/Index?handler=Read") references the OnPostRead or OnGetRead handler method in the Index page.

For more information on Razor Pages architecture and concepts, refer to the official Microsoft documentation.

Getting Started

To configure the CRUD operations in the FileManager within a Razor Pages application, follow the next steps:

  1. Specify the Read, Create, Update, and Destroy options of the DataSource configuration. The URL in each of these options must refer to the method name in the PageModel.

    Razor
        @page
        @model IndexModel
    
        @(Html.Kendo().FileManager()
            .Name("filemanager")
            .DataSource(ds =>
                {
                    ds.Read(operation => operation
                    .Type(HttpVerbs.Post)
                    .Url(Url.Page("Index", "FileManagerRead"))
                    .Data("forgeryToken")
                );
                ds.Destroy(operation => operation
                    .Type(HttpVerbs.Post)
                    .Url(Url.Page("Index", "FileManagerDestroy"))
                    .Data("forgeryToken")
                );
                ds.Create(operation => operation
                    .Type(HttpVerbs.Post)
                    .Url(Url.Page("Index", "FileManagerCreate"))
                    .Data("forgeryToken")
                );
                ds.Update(operation => operation
                    .Type(HttpVerbs.Post)
                    .Url(Url.Page("Index", "FileManagerUpdate"))
                    .Data("forgeryToken")
                );
            })
            .UploadUrl("/Index?handler=FileManagerUpload")
        )
  2. Add an AntiForgeryToken at the top of the page.

    Razor
        @inject Microsoft.AspNetCore.Antiforgery.IAntiforgery Xsrf
        @Html.AntiForgeryToken()
  3. Send the AntiForgeryToken with the Read request.

    JavaScript
        <script>
            function forgeryToken() {
                return kendo.antiForgeryTokens();
            }
        </script>

    Additional parameters can also be supplied.

    JavaScript
        <script>
            function forgeryToken() {
                return {
                    __RequestVerificationToken: kendo.antiForgeryTokens().__RequestVerificationToken,
                    additionalParameter: "test"
                }
            }
        </script>
  4. Within the cshtml.cs file, add a handler method for each data operation.

    C#
    public class IndexModel : PageModel
    {
        public IndexModel(IWebHostEnvironment hostingEnvironment)
        {
            HostingEnvironment = hostingEnvironment;
            directoryBrowser = new FileContentBrowser();
        }
    
        protected readonly IWebHostEnvironment HostingEnvironment;
        private readonly FileContentBrowser directoryBrowser;
    
        public virtual JsonResult OnPostFileManagerRead(string target)
        {
            var path = NormalizePath(target);
            if (Authorize(path))
            {
                try
                {
                    var files = directoryBrowser.GetFiles(path, Filter);
                    var directories = directoryBrowser.GetDirectories(path);
                    var result = files.Concat(directories).Select(VirtualizePath);
                    return new JsonResult(result.ToArray());
                }
                catch (DirectoryNotFoundException)
                {
                    throw new Exception("File Not Found");
                }
            }
            throw new Exception("Forbidden");
        }
    
        public virtual ActionResult OnPostFileManagerCreate(string target, FileManagerEntry entry)
        {
            FileManagerEntry newEntry;
            if (!Authorize(NormalizePath(target)))
            {
                throw new Exception("Forbidden");
            }
    
            if (String.IsNullOrEmpty(entry.Path))
            {
                newEntry = CreateNewFolder(target, entry);
            }
            else
            {
                newEntry = CopyEntry(target, entry);
            }
            return new JsonResult(VirtualizePath(newEntry));
        }
    
        public virtual ActionResult OnPostFileManagerDestroy(FileManagerEntry entry)
        {
            var path = NormalizePath(entry.Path);
            if (!string.IsNullOrEmpty(path))
            {
                if (entry.IsDirectory)
                {
                    DeleteDirectory(path);
                }
                else
                {
                    DeleteFile(path);
                }
                return new JsonResult(new object[0]);
            }
            throw new Exception("File Not Found");
        }
    
        public virtual ActionResult OnPostFileManagerUpdate(string target, FileManagerEntry entry)
        {
            FileManagerEntry newEntry;
            if (!Authorize(NormalizePath(entry.Path)) && !Authorize(NormalizePath(target)))
            {
                throw new Exception("Forbidden");
            }
            newEntry = RenameEntry(entry);
            return new JsonResult(VirtualizePath(newEntry));
        }
    }

For the complete project, refer to the FileManager in Razor Pages example.

See Also