How to extend functionality of TextNode and RichTextNode classes in WinForms Diagram?

The first step is to create the custom Text or RichText node types in your application by subclassing the base Essential® Diagram TextNode or RichTextNode classes. Once the custom text node has been defined, you will have to initialize the Diagram Text/RichTextTool to use this class in place of the default TextNode/RichTextNode. This is done by accessing the TextTool/RichTextTool from the Diagram's Controller using the Controller.GetTool(string toolName) with 'TextTool'/'RichTextTool' as the tool name, and initializing its TextTool.TextFactory/RichTextTool.RichTextFactory property with a delegate that creates the derived TextNode/RichTextNode type. A sample factory delegate is shown below:

// Factory method for creating rich text nodes for the RichTextTool.
protected RichTextNode MyRichTextFactory(RectangleF bounds, string text)
{
    Syncfusion.Windows.Forms.Diagram.RichTextNode rtfNode = new MyRichTextNode("Rich Text");
    rtfNode.Bounds = bounds;
    return rtfNode;
}

VB

' Factory method for creating rich text nodes for the RichTextTool.
Protected Function MyRichTextFactory(ByVal bounds As RectangleF, ByVal text As String) As RichTextNode
    Dim rtfNode As Syncfusion.Windows.Forms.Diagram.RichTextNode = New MyRichTextNode("Rich Text")
    rtfNode.Bounds = bounds
    Return rtfNode
End Function