Since TX Text Control .NET Server 30.0 supports .NET 5 and .NET 6, the components can be used in Blazor Server Apps. This article shows how to save a document using the document editor and to modify the document server-side using the ServerTextControl class.

Data Flow

The following dialog shows the data flow in this concept. The JavaScript API of TX Text Control is used to save the document which is transferred to .NET (the "server"). In .NET, the document is processed using an instance of ServerTextControl and is sent back to client-side by invoking a JavaScript function that loads the content back into the TX Text Control document editor.

Server-side, the document is loaded and modified by adding the text "This document has been modified by .NET" to the beginning of the document before it is loaded back into the editor.

The Required Code

The following code shows the editor page that consists of the document editor and a button:

@page "/editor"
@inject IJSRuntime JSRuntime

<h1>Send Document to .NET</h1>

<style>
        
        #txDocumentEditorContainer {
            width: 1100px;
            height: 600px;
            display: inline-block;
            position: relative;
        }
        
</style>
        
<div id="txDocumentEditorContainer" @ref="txDocumentEditorContainer"></div>

<br />

<button @onclick="SaveDocument">
        Save and Reload Document
</button>

@code
{
        private ElementReference txDocumentEditorContainer;

        protected override async Task OnAfterRenderAsync(bool firstRender) {
                if (firstRender) {
                        await JSRuntime.InvokeVoidAsync("addEditorToElement", txDocumentEditorContainer);
                }
        }

        private void SaveDocument()
        {
                // create a .NET object and call the 'saveDocument' JS function
                var dotNetReference = DotNetObjectReference.Create(this);
                JSRuntime.InvokeVoidAsync("TextControl.saveDocument", dotNetReference);
        }

        [JSInvokable("ProcessDocument")]
        public void ProcessDocument(string document)
        {
                byte[] bDocument;

                // create a ServerTextControl instance to load the saved document
                using (TXTextControl.ServerTextControl tx = new  TXTextControl.ServerTextControl()) {
                        tx.Create();
                        tx.Load(Convert.FromBase64String(document), TXTextControl.BinaryStreamType.InternalUnicodeFormat);
                        
                        // add additional text to the document
                        tx.Selection.Text = "This document has been modified by .NET\r\n";
                        
                        // save back
                        tx.Save(out bDocument, TXTextControl.BinaryStreamType.InternalUnicodeFormat);
                }

                // invoke the JS function 'loadDocument' to load back to the modified document
                JSRuntime.InvokeVoidAsync("TextControl.loadDocument", bDocument);
        }

}

When clicking the button, a DotNetObjectReference object is created and invoked with the TextControl.saveDocument JavaScript method. In this method, the document is saved and passed to the .NET method ProcessDocument (see code above).

var TextControl = TextControl || {};

TextControl.saveDocument = function (dotNetObject) {

        // save the document on TXTextControl object
        TXTextControl.saveDocument(TXTextControl.StreamType.InternalUnicodeFormat, function (document) {
                // call the .NET method 'ProcessDocument' with the saved document data
                dotNetObject.invokeMethodAsync('ProcessDocument', document.data);
        });

};

TextControl.loadDocument = function (document) {

        // load the document back into the editor (TXTextControl)
        TXTextControl.loadDocument(TXTextControl.StreamType.InternalUnicodeFormat, document);

};

In the .NET method ProcessDocument, the saved document is loaded into a ServerTextControl instance to add additional text. Finally, it is saved back by invoking another JavaScript method TextControl.loadDocument to load the modified document into the document editor.

Conclusion

This data flow shows how to use the document editor and the server-side non-UI components of TX Text Control in combination in Blazor Server Apps.

You can test this data flow using the sample project that is hosted in our GitHub account.