Express.js Application

  • 4 minutes to read

This topic describes how to add the client-side RichEdit control to an Express application.

Prerequisites

Requirements

  • To use the RichEdit control in an Express application, you need to have a Universal, DXperience, or ASP.NET subscription.
  • Versions of the devexpress npm packages should be identical (their major and minor versions should be the same).

Create an Express Application with RichEdit

Install a RichEdit Package

The devexpress-richedit npm package references devextreme as peerDependencies. The peerDependencies packages should be installed manually. This allows developers to control a version of the peerDependencies packages and guarantees that the package is installed once.

Install a RichEdit package with required peerDependencies:

  1. If the package.json file does not exist, create an npm configuration file as follows: npm init -y
  2. Install a RichEdit package with required peerDependencies:

    npm i devextreme devexpress-richedit --save
    

You can find all the libraries in the node_modules folder after the installation is completed.

Create a RichEdit Bundle

Create a RichEdit Bundle.

cd node_modules/devexpress-richedit
npm i --save-dev
npm run build-custom
cd ../..

Install the Express Package

npm i --save express body-parser

Create the Express Server

Create the main.js file and populate it with the following content.

const path = require('path');
const fs = require('fs');
const express = require('express');
const bodyParser = require('body-parser');

const app = express();
const port = 3000;

app.use(express.static('public'));
app.use(express.static(path.join('node_modules', 'devexpress-richedit', 'dist', 'custom')));
app.use(bodyParser.urlencoded({ extended: true })); // support encoded bodies

app.post('/api/SaveDocument', function (req, res) {
    var fileAsBase64 = req.body.base64;
    var fileName = req.body.fileName;
    var format = req.body.format;
    var reason = req.body.reason;
    fs.writeFile(`${fileName}.${getDocumentExtension(format)}`, fileAsBase64, 'base64', (err) => { });
    res.sendStatus(200);
});

app.listen(port, () => console.log(`Example app listening at http://localhost:${port}`));

function getDocumentExtension(format) {
    switch (format) {
        case '4': return "docx";
        case '2': return "rtf";
        case '1': return "txt";
    }
    return "docx";
}

Create the Main Page

Create the public/index.html file and populate it with the following content.

<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>RichEdit Express App</title>

    <link rel="stylesheet" type="text/css" href="dx.richedit.css" />
    <script src="https://code.jquery.com/jquery-3.5.1.min.js"></script>
    <script src="dx.richedit.js"></script>
    <script src="richedit-creator.js"></script>

    <script>
        $(document).ready(function () {
            createRichEdit('api/SaveDocument');
        });
    </script>
</head>
<body>
    <div id='rich-container' style="width: 100%; height: 900px"></div>
</body>
</html>

Create RichEdit Object

Create the public/richedit-creator.js file and populate it with the following content.

/// <reference path="../node_modules/devexpress-richedit/dist/dx.richedit.d.ts" />
function createRichEdit(exportUrl) {
    const options = DevExpress.RichEdit.createOptions();

    options.bookmarks.visibility = true;
    options.bookmarks.color = '#ff0000';

    options.confirmOnLosingChanges.enabled = true;
    options.confirmOnLosingChanges.message = 'Are you sure you want to perform the action? All unsaved document data will be lost.';

    options.fields.updateFieldsBeforePrint = true;
    options.fields.updateFieldsOnPaste = true;

    options.mailMerge.activeRecord = 2;
    options.mailMerge.viewMergedData = true;
    options.mailMerge.dataSource = [
        { Name: 'Indy', age: 32 },
        { Name: 'Andy', age: 28 },
    ];

    // events
    options.events.activeSubDocumentChanged = () => { };
    options.events.autoCorrect = () => { };
    options.events.calculateDocumentVariable = () => { };
    options.events.characterPropertiesChanged = () => { };
    options.events.contentInserted = () => { };
    options.events.contentRemoved = () => { };
    options.events.documentChanged = () => { };
    options.events.documentFormatted = () => { };
    options.events.documentLoaded = () => { };
    options.events.gotFocus = () => { };
    options.events.hyperlinkClick = () => { };
    options.events.keyDown = () => { };
    options.events.keyUp = () => { };
    options.events.paragraphPropertiesChanged = () => { };
    options.events.lostFocus = () => { };
    options.events.pointerDown = () => { };
    options.events.pointerUp = () => { };
    options.events.saving = () => { };
    options.events.saved = () => { };
    options.events.selectionChanged = () => { };    
    options.events.customCommandExecuted = (s, e) => {
        switch (e.commandName) {
        case 'insertEmailSignature':
            s.document.insertParagraph(s.document.length);
            s.document.insertText(s.document.length, '_________');
            s.document.insertParagraph(s.document.length);
            s.document.insertText(s.document.length, 'Best regards,');
            s.document.insertParagraph(s.document.length);
            s.document.insertText(s.document.length, 'John Smith');
            s.document.insertParagraph(s.document.length);
            s.document.insertText(s.document.length, 'john@example.com');
            s.document.insertParagraph(s.document.length);
            s.document.insertText(s.document.length, '+1 (818) 844-0000');
            break;
        }
    };

    options.view.viewType = DevExpress.RichEdit.ViewType.PrintLayout;
    options.view.simpleViewSettings.paddings = {
        left: 15,
        top: 15,
        right: 15,
        bottom: 15,
    };

    options.autoCorrect = {
        correctTwoInitialCapitals: true,
        detectUrls: true,
        enableAutomaticNumbering: true,
        replaceTextAsYouType: true,
        caseSensitiveReplacement: false,
        replaceInfoCollection: [
            { replace: "wnwd", with: "well-nourished, well-developed" },
            { replace: "(c)", with: "©" }
        ],
    };
    // capitalize the first letter at the beginning of a new sentence/line
    options.events.autoCorrect = function (s, e) {
        if (e.text.length == 1 && /\w/.test(e.text)) {
            var prevText = s.document.getText(new DevExpress.RichEdit.Interval(e.interval.start - 2, 2));
            if (prevText.length == 0 || /^(\. |\? |\! )$/.test(prevText) || prevText.charCodeAt(1) == 13) {
                var newText = e.text.toUpperCase();
                if (newText != e.text) {
                    s.beginUpdate();
                    s.history.beginTransaction();
                    s.document.deleteText(e.interval);
                    s.document.insertText(e.interval.start, newText);
                    s.history.endTransaction();
                    s.endUpdate();
                    e.handled = true;
                }
            }
        }
    };  

    options.exportUrl = exportUrl;

    options.readOnly = false;
    options.width = '1400px';
    options.height = '900px';

    var richElement = document.getElementById("rich-container");

    var richEdit = DevExpress.RichEdit.create(richElement, options);

    var documentAsBase64 = "e1xydGYxXGRlZmYwe1xmb250dGJse1xmMCBDYWxpYnJpO319e1xjb2xvcnRibCA7XHJlZDB"
        + "cZ3JlZW4wXGJsdWUyNTUgO1xyZWQyNTVcZ3JlZW4yNTVcYmx1ZTI1NSA7fXtcKlxkZWZjaHAgXGZzMjJ9e1xzdHl"
        + "sZXNoZWV0IHtccWxcZnMyMiBOb3JtYWw7fXtcKlxjczFcZnMyMiBEZWZhdWx0IFBhcmFncmFwaCBGb250O317XCp"
        + "cY3MyXGZzMjJcY2YxIEh5cGVybGluazt9e1wqXHRzM1x0c3Jvd2RcZnMyMlxxbFx0c3ZlcnRhbHRcdHNjZWxsY2J"
        + "wYXQyXHRzY2VsbHBjdDBcY2x0eGxydGIgTm9ybWFsIFRhYmxlO319e1wqXGxpc3RvdmVycmlkZXRhYmxlfXtcaW5"
        + "mb31cbm91aWNvbXBhdFxzcGx5dHduaW5lXGh0bWF1dHNwXGV4cHNocnRuXHNwbHRwZ3BhclxkZWZ0YWI3MjBcc2V"
        + "jdGRcbWFyZ2xzeG4xNDQwXG1hcmdyc3huMTQ0MFxtYXJndHN4bjE0NDBcbWFyZ2JzeG4xNDQwXGhlYWRlcnk3MjB"
        + "cZm9vdGVyeTcyMFxwZ3dzeG4xMjI0MFxwZ2hzeG4xNTg0MFxjb2xzMVxjb2xzeDcyMFxwYXJkXHBsYWluXHFse1x"
        + "mczIyXGNmMFxjczEgRG9jdW1lbnQgdGV4dH1cZnMyMlxjZjBccGFyfQ==";
    richEdit.openDocument(documentAsBase64, 'DocumentName', DevExpress.RichEdit.DocumentFormat.Rtf);
}

Launch the Application

Execute the node main.js command to launch the application.