Backend API
        
    import React, { useCallback, useState } from 'react';
import FileManager, {
  Permissions, ItemView, Details, Column, type FileManagerTypes,
} from 'devextreme-react/file-manager';
import RemoteFileSystemProvider from 'devextreme/file_management/remote_provider';
const remoteProvider = new RemoteFileSystemProvider({
  endpointUrl: 'https://js.devexpress.com/Demos/NetCore/api/file-manager-db',
});
const allowedFileExtensions = [];
export default function App() {
  const [currentPath, setCurrentPath] = useState('Documents/Reports');
  const onCurrentDirectoryChanged = useCallback((e: FileManagerTypes.CurrentDirectoryChangedEvent) => {
    setCurrentPath(e.component.option('currentPath'));
  }, []);
  return (
    <FileManager
      currentPath={currentPath}
      fileSystemProvider={remoteProvider}
      allowedFileExtensions={allowedFileExtensions}
      height={550}
      onCurrentDirectoryChanged={onCurrentDirectoryChanged}>
      <Permissions
        create={true}
        copy={true}
        move={true}
        delete={true}
        rename={true}>
      </Permissions>
      <ItemView>
        <Details>
          <Column dataField="thumbnail"></Column>
          <Column dataField="name"></Column>
          <Column dataField="dateModified" caption="Modified"></Column>
          <Column dataField="created" caption="Created" dataType="date"></Column>
          <Column dataField="modifiedBy" caption="Modified By" visibleIndex={2}></Column>
        </Details>
      </ItemView>
    </FileManager>
  );
}
    
    import React, { useCallback, useState } from 'react';
import FileManager, {
  Permissions, ItemView, Details, Column,
} from 'devextreme-react/file-manager';
import RemoteFileSystemProvider from 'devextreme/file_management/remote_provider';
const remoteProvider = new RemoteFileSystemProvider({
  endpointUrl: 'https://js.devexpress.com/Demos/NetCore/api/file-manager-db',
});
const allowedFileExtensions = [];
export default function App() {
  const [currentPath, setCurrentPath] = useState('Documents/Reports');
  const onCurrentDirectoryChanged = useCallback((e) => {
    setCurrentPath(e.component.option('currentPath'));
  }, []);
  return (
    <FileManager
      currentPath={currentPath}
      fileSystemProvider={remoteProvider}
      allowedFileExtensions={allowedFileExtensions}
      height={550}
      onCurrentDirectoryChanged={onCurrentDirectoryChanged}
    >
      <Permissions
        create={true}
        copy={true}
        move={true}
        delete={true}
        rename={true}
      ></Permissions>
      <ItemView>
        <Details>
          <Column dataField="thumbnail"></Column>
          <Column dataField="name"></Column>
          <Column
            dataField="dateModified"
            caption="Modified"
          ></Column>
          <Column
            dataField="created"
            caption="Created"
            dataType="date"
          ></Column>
          <Column
            dataField="modifiedBy"
            caption="Modified By"
            visibleIndex={2}
          ></Column>
        </Details>
      </ItemView>
    </FileManager>
  );
}
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.tsx';
ReactDOM.render(
  <App />,
  document.getElementById('app'),
);
    
    window.exports = window.exports || {};
window.config = {
  transpiler: 'ts',
  typescriptOptions: {
    module: 'system',
    emitDecoratorMetadata: true,
    experimentalDecorators: true,
    jsx: 'react',
  },
  meta: {
    'react': {
      'esModule': true,
    },
    'typescript': {
      'exports': 'ts',
    },
    'devextreme/time_zone_utils.js': {
      'esModule': true,
    },
    'devextreme/localization.js': {
      'esModule': true,
    },
    'devextreme/viz/palette.js': {
      'esModule': true,
    },
    'openai': {
      'esModule': true,
    },
  },
  paths: {
    'npm:': 'https://cdn.jsdelivr.net/npm/',
    'bundles:': '../../../../bundles/',
    'externals:': '../../../../bundles/externals/',
  },
  defaultExtension: 'js',
  map: {
    'ts': 'npm:plugin-typescript@8.0.0/lib/plugin.js',
    'typescript': 'npm:typescript@4.2.4/lib/typescript.js',
    'jszip': 'npm:jszip@3.10.1/dist/jszip.min.js',
    'react': 'npm:react@17.0.2/umd/react.development.js',
    'react-dom': 'npm:react-dom@17.0.2/umd/react-dom.development.js',
    'prop-types': 'npm:prop-types/prop-types.js',
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    'luxon': 'npm:luxon@3.4.4/build/global/luxon.min.js',
    'es6-object-assign': 'npm:es6-object-assign',
    'devextreme': 'npm:devextreme@link:../../packages/devextreme/artifacts/npm/devextreme/cjs',
    'devextreme-react': 'npm:devextreme-react@link:../../packages/devextreme-react/npm/cjs',
    'devextreme-quill': 'npm:devextreme-quill@1.7.6/dist/dx-quill.min.js',
    'devexpress-diagram': 'npm:devexpress-diagram@2.2.24/dist/dx-diagram.js',
    'devexpress-gantt': 'npm:devexpress-gantt@4.1.64/dist/dx-gantt.js',
    'inferno': 'npm:inferno@8.2.3/dist/inferno.min.js',
    'inferno-compat': 'npm:inferno-compat/dist/inferno-compat.min.js',
    'inferno-create-element': 'npm:inferno-create-element@8.2.3/dist/inferno-create-element.min.js',
    'inferno-dom': 'npm:inferno-dom/dist/inferno-dom.min.js',
    'inferno-hydrate': 'npm:inferno-hydrate/dist/inferno-hydrate.min.js',
    'inferno-clone-vnode': 'npm:inferno-clone-vnode/dist/inferno-clone-vnode.min.js',
    'inferno-create-class': 'npm:inferno-create-class/dist/inferno-create-class.min.js',
    'inferno-extras': 'npm:inferno-extras/dist/inferno-extras.min.js',
    '@preact/signals-core': 'npm:@preact/signals-core@1.8.0/dist/signals-core.min.js',
    'devextreme-cldr-data': 'npm:devextreme-cldr-data@1.0.3',
    // SystemJS plugins
    'plugin-babel': 'npm:systemjs-plugin-babel@0.0.25/plugin-babel.js',
    'systemjs-babel-build': 'npm:systemjs-plugin-babel@0.0.25/systemjs-babel-browser.js',
    // Prettier
    'prettier/standalone': 'npm:prettier@2.8.8/standalone.js',
    'prettier/parser-html': 'npm:prettier@2.8.8/parser-html.js',
  },
  packages: {
    'devextreme': {
      defaultExtension: 'js',
    },
    'devextreme-react': {
      main: 'index.js',
    },
    'devextreme-react/common': {
      main: 'index.js',
    },
    'devextreme/events/utils': {
      main: 'index',
    },
    'devextreme/common/core/events/utils': {
      main: 'index',
    },
    'devextreme/localization/messages': {
      format: 'json',
      defaultExtension: 'json',
    },
    'devextreme/events': {
      main: 'index',
    },
    'es6-object-assign': {
      main: './index.js',
      defaultExtension: 'js',
    },
  },
  packageConfigPaths: [
    'npm:@devextreme/*/package.json',
  ],
  babelOptions: {
    sourceMaps: false,
    stage0: true,
    react: true,
  },
};
System.config(window.config);
// eslint-disable-next-line
const useTgzInCSB = ['openai'];
    
    import React from 'react';
import ReactDOM from 'react-dom';
import App from './App.js';
ReactDOM.render(<App />, document.getElementById('app'));
    
    <!DOCTYPE html>
<html lang="en">
  <head>
    <title>DevExtreme Demo</title>
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=5.0" />
    <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/25.1.6/css/dx.light.css" />
    <link rel="stylesheet" type="text/css" href="https://cdn3.devexpress.com/jslib/25.1.6/css/dx-gantt.min.css" />
    <script src="https://cdn.jsdelivr.net/npm/core-js@2.6.12/client/shim.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/systemjs@0.21.3/dist/system.js"></script>
    <script type="text/javascript" src="config.js"></script>
    <script type="text/javascript">
      System.import("./index.tsx");
    </script>
      <link rel="stylesheet" type="text/css" href="styles.css" />
</head>
  <body class="dx-viewport">
    <div class="demo-container">
      <div id="app"></div>
    </div>
  </body>
</html>
    
    
    
    using DevExtreme.AspNet.Mvc.FileManagement;
using DevExtreme.MVC.Demos.Models.FileManagement;
using System;
using System.Web;
using System.Web.Http;
namespace DevExtreme.MVC.Demos.Controllers.ApiControllers {
    public class FileManagerDbProviderApiController : ApiController {
        [AcceptVerbs("GET", "POST")]
        [Route("api/file-manager-db", Name = "FileManagerDBProviderApi")]
        public object Process(FileSystemCommand command, string arguments) {
            var request = new HttpContextWrapper(HttpContext.Current).Request;
            var config = new FileSystemConfiguration {
                Request = request,
                FileSystemProvider = new DbFileProvider(),
                AllowCopy = true,
                AllowCreate = true,
                AllowMove = true,
                AllowDelete = true,
                AllowRename = true,
                AllowedFileExtensions = new string[0]
            };
            var processor = new FileSystemCommandProcessor(config);
            var result = processor.Execute(command, arguments);
            return Ok(result.GetClientCommandResult());
        }
    }
}
    
    using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using DevExtreme.AspNet.Mvc.FileManagement;
namespace DevExtreme.MVC.Demos.Models.FileManagement {
    public class DbFileProvider : IFileSystemItemLoader, IFileSystemItemEditor {
        const int GuestPersonId = 1;
        public DbFileProvider() {
            FileManagementDbContext = new InMemoryFileManagementDataContext();
        }
        InMemoryFileManagementDataContext FileManagementDbContext { get; }
        public IEnumerable<FileSystemItem> GetItems(FileSystemLoadItemOptions options) {
            int parentId = ParseKey(options.Directory.Key);
            var fileItems = GetDirectoryContents(parentId);
            var hasSubDirectoriesInfo = GetHasSubDirectoriesInfo(fileItems);
            var clientItemList = new List<FileSystemItem>();
            foreach(var item in fileItems) {
                var clientItem = new FileSystemItem {
                    Key = item.Id.ToString(),
                    Name = item.Name,
                    IsDirectory = item.IsDirectory,
                    DateModified = item.Modified
                };
                if(item.IsDirectory) {
                    clientItem.HasSubDirectories = hasSubDirectoriesInfo.ContainsKey(item.Id) && hasSubDirectoriesInfo[item.Id];
                }
                clientItem.CustomFields["modifiedBy"] = item.ModifiedBy.FullName;
                clientItem.CustomFields["created"] = item.Created;
                clientItemList.Add(clientItem);
            }
            return clientItemList;
        }
        public void CreateDirectory(FileSystemCreateDirectoryOptions options) {
            var parentDirectory = options.ParentDirectory;
            if(!IsFileItemExists(parentDirectory))
                ThrowItemNotFoundException(parentDirectory);
            var directory = new FileItem {
                Name = options.DirectoryName,
                Modified = DateTime.Now,
                Created = DateTime.Now,
                IsDirectory = true,
                ParentId = ParseKey(parentDirectory.Key),
                ModifiedById = GuestPersonId
            };
            FileManagementDbContext.FileItems.Add(directory);
            FileManagementDbContext.SaveChanges();
        }
        public void RenameItem(FileSystemRenameItemOptions options) {
            var item = options.Item;
            if(!IsFileItemExists(item))
                ThrowItemNotFoundException(item);
            var fileItem = GetFileItem(item);
            fileItem.Name = options.ItemNewName;
            fileItem.ModifiedById = GuestPersonId;
            fileItem.Modified = DateTime.Now;
            FileManagementDbContext.SaveChanges();
        }
        public void MoveItem(FileSystemMoveItemOptions options) {
            var item = options.Item;
            var destinationDirectory = options.DestinationDirectory;
            if(!IsFileItemExists(item))
                ThrowItemNotFoundException(item);
            if(!IsFileItemExists(destinationDirectory))
                ThrowItemNotFoundException(destinationDirectory);
            if(!AllowCopyOrMove(item, destinationDirectory))
                ThrowNoAccessException();
            var fileItem = GetFileItem(item);
            fileItem.ParentId = ParseKey(destinationDirectory.Key);
            fileItem.Modified = DateTime.Now;
            fileItem.ModifiedById = GuestPersonId;
            FileManagementDbContext.SaveChanges();
        }
        public void CopyItem(FileSystemCopyItemOptions options) {
            var item = options.Item;
            var destinationDirectory = options.DestinationDirectory;
            if(!IsFileItemExists(item))
                ThrowItemNotFoundException(item);
            if(!IsFileItemExists(destinationDirectory))
                ThrowItemNotFoundException(destinationDirectory);
            if(!AllowCopyOrMove(item, destinationDirectory))
                ThrowNoAccessException();
            var sourceFileItem = GetFileItem(item);
            var copyFileItem = CreateCopy(sourceFileItem);
            copyFileItem.ParentId = ParseKey(destinationDirectory.Key);
            copyFileItem.Name = GenerateCopiedFileItemName(copyFileItem.ParentId, copyFileItem.Name, copyFileItem.IsDirectory);
            FileManagementDbContext.FileItems.Add(copyFileItem);
            if(copyFileItem.IsDirectory)
                CopyDirectoryContentRecursive(sourceFileItem, copyFileItem);
            FileManagementDbContext.SaveChanges();
        }
        void CopyDirectoryContentRecursive(FileItem sourcePathInfo, FileItem destinationPathInfo) {
            foreach(var fileItem in GetDirectoryContents(sourcePathInfo.Id)) {
                var copyItem = CreateCopy(fileItem);
                copyItem.Parent = destinationPathInfo;
                FileManagementDbContext.FileItems.Add(copyItem);
                if(fileItem.IsDirectory)
                    CopyDirectoryContentRecursive(fileItem, copyItem);
            }
        }
        public void DeleteItem(FileSystemDeleteItemOptions options) {
            var item = options.Item;
            if(!IsFileItemExists(item))
                ThrowItemNotFoundException(item);
            var fileItem = GetFileItem(item);
            FileManagementDbContext.FileItems.Remove(fileItem);
            if(fileItem.IsDirectory)
                RemoveDirectoryContentRecursive(fileItem.Id);
            FileManagementDbContext.SaveChanges();
        }
        void RemoveDirectoryContentRecursive(int parenDirectoryKey) {
            var itemsToRemove = FileManagementDbContext
                .FileItems
                .Where(item => item.ParentId == parenDirectoryKey)
                .Select(item => new FileItem {
                    Id = item.Id,
                    IsDirectory = item.IsDirectory
                });
            foreach(var item in itemsToRemove) {
                FileManagementDbContext.FileItems.Remove(item);
            }
            foreach(var item in itemsToRemove) {
                if(!item.IsDirectory) continue;
                RemoveDirectoryContentRecursive(item.Id);
            }
        }
        IEnumerable<FileItem> GetDirectoryContents(int parentKey) {
            return FileManagementDbContext.FileItems
                .OrderByDescending(item => item.IsDirectory)
                .ThenBy(item => item.Name)
                .Where(items => items.ParentId == parentKey);
        }
        IDictionary<int, bool> GetHasSubDirectoriesInfo(IEnumerable<FileItem> fileItems) {
            var keys = fileItems.Select(i => i.Id).ToArray();
            return FileManagementDbContext.FileItems
                .Where(item => item.IsDirectory)
                .GroupBy(i => i.ParentId)
                .Where(i => keys.Contains(i.Key))
                .ToDictionary(group => group.Key, group => group.Any());
        }
        FileItem GetFileItem(FileSystemItemInfo item) {
            var itemId = ParseKey(item.Key);
            return FileManagementDbContext.FileItems.FirstOrDefault(i => i.Id == itemId);
        }
        bool IsFileItemExists(FileSystemItemInfo itemInfo) {
            var pathKeys = itemInfo.PathKeys.Select(key => ParseKey(key)).ToArray();
            var foundEntries = FileManagementDbContext.FileItems
                .Where(item => pathKeys.Contains(item.Id))
                .Select(item => new { item.Id, item.ParentId, item.Name, item.IsDirectory });
            var pathNames = itemInfo.Path.Split(new[] { Path.DirectorySeparatorChar }, StringSplitOptions.RemoveEmptyEntries);
            var isDirectoryExists = true;
            for(var i = 0; i < pathKeys.Length && isDirectoryExists; i++) {
                var entry = foundEntries.FirstOrDefault(e => e.Id == pathKeys[i]);
                isDirectoryExists = entry != null && entry.Name == pathNames[i] &&
                                    (i == 0 && entry.ParentId == 0 || entry.ParentId == pathKeys[i - 1]);
                if(isDirectoryExists && i < pathKeys.Length - 1)
                    isDirectoryExists = entry.IsDirectory;
            }
            return isDirectoryExists;
        }
        static bool AllowCopyOrMove(FileSystemItemInfo item, FileSystemItemInfo destinationDirectory) {
            if(destinationDirectory.PathKeys.Length < item.PathKeys.Length)
                return true;
            var isValid = false;
            for(var i = 0; i < destinationDirectory.PathKeys.Length && !isValid; i++) {
                isValid = destinationDirectory.PathKeys[i] != item.PathKeys[i];
            }
            return isValid;
        }
        static FileItem CreateCopy(FileItem fileItem) {
            return new FileItem {
                Name = fileItem.Name,
                Created = DateTime.Now,
                Modified = DateTime.Now,
                IsDirectory = fileItem.IsDirectory,
                ModifiedById = GuestPersonId
            };
        }
        static int ParseKey(string key) {
            return string.IsNullOrEmpty(key) ? 0 : int.Parse(key);
        }
        string GenerateCopiedFileItemName(int parentDirKey, string copiedFileItemName, bool isDirectory) {
            var dirNames = GetDirectoryContents(parentDirKey)
                .Where(i => i.IsDirectory == isDirectory)
                .Select(i => i.Name);
            string newName;
            var fileExtension = isDirectory ? "" : "." + Path.GetExtension(copiedFileItemName);
            var copyNamePrefix =
                isDirectory ? copiedFileItemName : Path.GetFileNameWithoutExtension(copiedFileItemName);
            var index = -1;
            do {
                var pathPostfix = index < 1 ? string.Empty : $" {index}{fileExtension}";
                newName = $"{copyNamePrefix} {(index < 0 ? "" : "copy")}{pathPostfix}";
                index++;
            } while(dirNames.Contains(newName));
            return newName;
        }
        void ThrowItemNotFoundException(FileSystemItemInfo item) {
            var itemType = item.IsDirectory ? "Directory" : "File";
            var errorCode = item.IsDirectory ? FileSystemErrorCode.DirectoryNotFound : FileSystemErrorCode.FileNotFound;
            string message = $"{itemType} '{item.Path}' not found.";
            throw new FileSystemException(errorCode, message);
        }
        void ThrowNoAccessException() {
            string message = "Access denied. The operation cannot be completed.";
            throw new FileSystemException(FileSystemErrorCode.NoAccess, message);
        }
    }
}