Getting Started with ASP.NET Core RichTextEditor Control

21 Dec 202222 minutes to read

This section briefly explains about how to include ASP.NET Core RichTextEditor control in your ASP.NET Core application using Visual Studio.

Prerequisites

System requirements for ASP.NET Core controls

Create ASP.NET Core web application with Razor pages

Install ASP.NET Core package in the application

Syncfusion ASP.NET Core controls are available in nuget.org. Refer to NuGet packages topic to learn more about installing NuGet packages in various OS environments. To add ASP.NET Core controls in the application, open the NuGet package manager in Visual Studio (Tools → NuGet Package Manager → Manage NuGet Packages for Solution), search for Syncfusion.EJ2.AspNet.Core and then install it.

NOTE

The Syncfusion.EJ2.AspNet.Core NuGet package has dependencies, Newtonsoft.Json for JSON serialization and Syncfusion.Licensing for validating Syncfusion license key.

Add Syncfusion ASP.NET Core Tag Helper

Open ~/Views/_ViewImports.cshtml file and import the Syncfusion.EJ2 TagHelper.

~/_ViewImports.cshtml
@addTagHelper *, Syncfusion.EJ2

Add style sheet

Checkout the Themes topic to learn different ways (CDN, NPM package, and CRG) to refer styles in ASP.NET Core application, and to have the expected appearance for Syncfusion ASP.NET Core controls. Here, the theme is referred using CDN inside the <head> of ~/Pages/Shared/_Layout.cshtml file as follows,

~/_Layout.cshtml
<head>
    ...
    <!-- Syncfusion ASP.NET Core controls styles -->
    <link rel="stylesheet" href="https://cdn.syncfusion.com/ej2/21.1.35/fluent.css" />
</head>

Add script reference

In this getting started walk-through, the required scripts are referred using CDN inside the <head> of ~/Pages/Shared/_Layout.cshtml file as follows,

~/_Layout.cshtml
<head>
    ...
    <!-- Syncfusion ASP.NET Core controls scripts -->
    <script src="https://cdn.syncfusion.com/ej2/21.1.35/dist/ej2.min.js"></script>
</head>

Register Syncfusion Script Manager

Open ~/Pages/Shared/_Layout.cshtml page and register the script manager at the end of `<body>` in the ASP.NET Core application as follows.

~/_Layout.cshtml
<body>
    ....
    ....
    <!-- Syncfusion ASP.NET Core Script Manager -->
    <ejs-scripts></ejs-scripts>
</body>

Add ASP.NET Core RichTextEditor control

Now, add the Syncfusion ASP.NET Core RichTextEditor tag helper in ~/Pages/Index.cshtml page.

CSHTML
<ejs-richtexteditor id="defaultRTE">
    <e-content-template>
        <div>
            <p>The Rich Text Editor is WYSIWYG ('what you see is what you get') editor useful to create and edit content, and return the valid <a href='https://ej2.syncfusion.com/aspnetcore/RichTextEditor/Overview'>HTML markup</a> or <a href='https://ej2.syncfusion.com/aspnetcore/RichTextEditor/DefaultMode'>markdown</a> of the content</p>
            <p><b> Toolbar </b></p>
            <ol>
                <li>
                    <p> Toolbar contains commands to align the text, insert link, insert image, insert list, undo / redo operations, HTML view, etc </p>
                </li>
                <li>
                    <p> Toolbar is fully customizable </p>
                </li>
            </ol>
            <p><b> Links </b></p>
            <ol>
                <li>
                    <p> You can insert a hyperlink with its corresponding dialog</p>
                </li>
                <li>
                    <p> Attach a hyperlink to the displayed text. </p>
                </li>
                <li>
                    <p> Customize the quick toolbar based on the hyperlink </p>
                </li>
            </ol>
            <p><b> Image.</b></p>
            <ol>
                <li>
                    <p> Allows you to insert images from an online source as well as the local computer</p>
                </li>
                <li>
                    <p> You can upload an image</p>
                </li>
                <li>
                    <p> Provides an option to customize quick toolbar for an image </p>
                </li>
            </ol>
        </div>
    </e-content-template>
</ejs-richtexteditor>

Press Ctrl+F5 (Windows) or ⌘+F5 (macOS) to run the app. Then, the Syncfusion ASP.NET Core RichTextEditor control will be rendered in the default web browser.

ASP.NET Core RichTextEditor Control

Initialize from iframe element

Initialize the Rich Text Editor on <div> element as shown below and set the enable field of iframeSettings property as true to render the Rich Text Editor content in an <iframe> and its isolated from the rest of the page.

CSHTML
<ejs-richtexteditor id="iframe">
    <e-richtexteditor-iframesettings enable="true"></e-richtexteditor-iframesettings>
    <e-content-template>
        <p>
            The Rich Text Editor control is WYSIWYG ('what you see is what you get') editor that provides the best user experience to create and update the content.
            Users can format their content using standard toolbar commands.
        </p>
        <p><b> Key features:</b></p>

        <ul>
            <li><p> Provides &lt; IFRAME &gt; and &lt; DIV &gt; modes </p></li>
            <li><p> Capable of handling markdown editing.</p></li>
            <li><p> Contains a modular library to load the necessary functionality on demand.</p></li>
            <li><p> Provides a fully customizable toolbar.</p></li>
            <li><p> Provides HTML view to edit the source directly for developers.</p></li>
            <li><p> Supports third - party library integration.</p></li>
            <li><p> Allows preview of modified content before saving it.</p></li>
            <li><p> Handles images, hyperlinks, video, hyperlinks, uploads, etc.</p></li>
            <li><p> Contains undo / redo manager.</p></li>
            <li><p> Creates bulleted and numbered lists.</p></li>
        </ul>
    </e-content-template>
</ejs-richtexteditor>

ASP.NET Core RichTextEditor with Iframe Element

Configure the toolbar with the tools using items field of the toolbarSettings property as your application requires.

CSHTML
@{
    .....
    var tools = new[] {
        "Bold", "Italic", "Underline", "StrikeThrough",
        "FontName", "FontSize", "FontColor", "BackgroundColor",
        "LowerCase", "UpperCase", "|",
        "Formats", "Alignments", "OrderedList", "UnorderedList",
        "Outdent", "Indent", "|",
        "CreateLink", "Image", "CreateTable", "|", "ClearFormat", "Print",
        "SourceCode", "FullScreen", "|", "Undo", "Redo"
            };
}

<ejs-richtexteditor id="toolbar">
    <e-richtexteditor-toolbarsettings items="tools"></e-richtexteditor-toolbarsettings>
    <e-content-template>
        <p>
            The Rich Text Editor control is WYSIWYG ('what you see is what you get') editor that provides the best user experience to create and update the content.
            Users can format their content using standard toolbar commands.
        </p>
        <p><b> Key features:</b></p>

        <ul>
            <li><p> Provides &lt; IFRAME &gt; and &lt; DIV &gt; modes </p></li>
            <li><p> Capable of handling markdown editing.</p></li>
            <li><p> Contains a modular library to load the necessary functionality on demand.</p></li>
            <li><p> Provides a fully customizable toolbar.</p></li>
            <li><p> Provides HTML view to edit the source directly for developers.</p></li>
            <li><p> Supports third - party library integration.</p></li>
            <li><p> Allows preview of modified content before saving it.</p></li>
            <li><p> Handles images, hyperlinks, video, hyperlinks, uploads, etc.</p></li>
            <li><p> Contains undo / redo manager.</p></li>
            <li><p> Creates bulleted and numbered lists.</p></li>
        </ul>
    </e-content-template>
</ejs-richtexteditor>

ASP.NET Core RichTextEditor with Toolbar

NOTE

| and - can insert a vertical and horizontal separator lines in the toolbar.

Insert Images and Links

The Image module inserts an image into RichTextEditor’s content area, and the Link module links external resources such as website URLs, to selected text in the RichTextEditor’s content, respectively.

The link inject module adds a link icon to the toolbar and the image inject module adds an image icon to the toolbar.

Specifies the items to be rendered in quick toolbar based on the target element such image, link and text element. The quick toolbar opens to customize the element by clicking the target element.

CSHTML
@{
    .....
	var image = new[] {
        "Replace", "Align", "Caption", "Remove", "InsertLink", "OpenImageLink", "-",
        "EditImageLink", "RemoveImageLink", "Display", "AltText", "Dimension"
            };
    var tools = new[] {
        "Bold", "Italic", "Underline", "StrikeThrough",
        "FontName", "FontSize", "FontColor", "BackgroundColor",
        "LowerCase", "UpperCase", "|",
        "Formats", "Alignments", "OrderedList", "UnorderedList",
        "Outdent", "Indent", "|",
        "CreateLink", "Image", "CreateTable", "|", "ClearFormat", "Print",
        "SourceCode", "FullScreen", "|", "Undo", "Redo"
            };
}

<ejs-richtexteditor id="image">
    <e-richtexteditor-quicktoolbarsettings image="@ViewBag.image"></e-richtexteditor-quicktoolbarsettings>
    <e-richtexteditor-toolbarsettings items="@ViewBag.tools"></e-richtexteditor-toolbarsettings>
    <e-content-template>
        <p>
            The Rich Text Editor control is WYSIWYG ('what you see is what you get') editor that provides the best user experience to create and update the content.
            Users can format their content using standard toolbar commands.
        </p>
        <p><b> Key features:</b></p>

        <ul>
            <li><p> Provides &lt; IFRAME &gt; and &lt; DIV &gt; modes </p></li>
            <li><p> Capable of handling markdown editing.</p></li>
            <li><p> Contains a modular library to load the necessary functionality on demand.</p></li>
            <li><p> Provides a fully customizable toolbar.</p></li>
            <li><p> Provides HTML view to edit the source directly for developers.</p></li>
            <li><p> Supports third - party library integration.</p></li>
            <li><p> Allows preview of modified content before saving it.</p></li>
            <li><p> Handles images, hyperlinks, video, hyperlinks, uploads, etc.</p></li>
            <li><p> Contains undo / redo manager.</p></li>
            <li><p> Creates bulleted and numbered lists.</p></li>
        </ul>
    </e-content-template>
</ejs-richtexteditor>

Send formatted content using XmlHttpRequest

The Html string of the Rich Text Editor can be passed from View to the Controller through the XMLHttpRequest Post action. The HTML value binds to the corresponding mapped controller, and you can access it in the Post action parameter.

CSHTML
CSHTML.cs
<ejs-richtexteditor id="defaultRTE">
    <e-content-template>
        <div>
            <p>The Rich Text Editor is WYSIWYG ('what you see is what you get') editor useful to create and edit content, and return the valid <a href='https://ej2.syncfusion.com/aspnetcore/RichTextEditor/Overview'>HTML markup</a> or <a href='https://ej2.syncfusion.com/aspnetcore/RichTextEditor/DefaultMode'>markdown</a> of the content</p>
            <p><b> Toolbar </b></p>
            <ol>
                <li>
                    <p> Toolbar contains commands to align the text, insert link, insert image, insert list, undo / redo operations, HTML view, etc </p>
                </li>
                <li>
                    <p> Toolbar is fully customizable </p>
                </li>
            </ol>
            <p><b> Links </b></p>
            <ol>
                <li>
                    <p> You can insert a hyperlink with its corresponding dialog</p>
                </li>
                <li>
                    <p> Attach a hyperlink to the displayed text. </p>
                </li>
                <li>
                    <p> Customize the quick toolbar based on the hyperlink </p>
                </li>
            </ol>
            <p><b> Image.</b></p>
            <ol>
                <li>
                    <p> Allows you to insert images from an online source as well as the local computer</p>
                </li>
                <li>
                    <p> You can upload an image</p>
                </li>
                <li>
                    <p> Provides an option to customize quick toolbar for an image </p>
                </li>
            </ol>
        </div>
    </e-content-template>
</ejs-richtexteditor>

<button id="getRTEvalue">Get RichTextEditor Value</button>

<script>
    document.getElementById('getRTEvalue').addEventListener('click', function () {
        var obj = document.getElementById('defaultRTE').ej2_instances[0];
        alert(obj.value);
    });
</script>
public class RichTextEditorValue
{
    public string text { get; set; }
}

Retrieve the Formatted Content

To retrieve the editor contents, use value property of Rich Text Editor.

  var rteValue = this.rteObj.value;

Or, you can use the public method, getHtml to retrieve the Rich Text Editor content.

  var rteValue = this.rteObj.getHtml();

To fetch the Rich Text Editor’s text content, use getText method of Rich Text Editor.

  var rteValue = this.rteObj.getText();

Retrieve the number of characters

To get the maximum number of characters in the Rich Text Editor’s content, use getCharCount

  let rteCount = this.rteObj.getCharCount();

The final output will be displayed as follows

CSHTML
@{
    .....
    var tools = new[] {
        "Bold", "Italic", "Underline", "StrikeThrough",
        "FontName", "FontSize", "FontColor", "BackgroundColor",
        "LowerCase", "UpperCase", "|",
        "Formats", "Alignments", "OrderedList", "UnorderedList",
        "Outdent", "Indent", "|",
        "CreateLink", "Image", "CreateTable", "|", "ClearFormat", "Print",
        "SourceCode", "FullScreen", "|", "Undo", "Redo"
            };
}
<ejs-richtexteditor id="link">
    <e-richtexteditor-toolbarsettings items="tools"></e-richtexteditor-toolbarsettings>
    <e-content-template>
        <p>
            The Rich Text Editor control is WYSIWYG ('what you see is what you get') editor that provides the best user experience to create and update the content.
            Users can format their content using standard toolbar commands.
        </p>
        <p><b> Key features:</b></p>

        <ul>
            <li><p> Provides &lt; IFRAME &gt; and &lt; DIV &gt; modes </p></li>

            <li><p> Capable of handling markdown editing.</p></li>

            <li><p> Contains a modular library to load the necessary functionality on demand.</p></li>

            <li><p> Provides a fully customizable toolbar.</p></li>

            <li><p> Provides HTML view to edit the source directly for developers.</p></li>

            <li><p> Supports third - party library integration.</p></li>

            <li><p> Allows preview of modified content before saving it.</p></li>

            <li><p> Handles images, hyperlinks, video, hyperlinks, uploads, etc.</p></li>

            <li><p> Contains undo / redo manager.</p></li>

            <li><p> Creates bulleted and numbered lists.</p></li>

        </ul>
    </e-content-template>
</ejs-richtexteditor>

NOTE

View Sample in GitHub.