n C# WinForms, the HasMorePages property is commonly used in combination with the PrintDocument class to navigate through multiple pages when printing or previewing content. However, the RichTextBox control itself does not have a built-in pagination mechanism or a direct HasMorePages property.

To achieve pagination within a RichTextBox, you can implement a custom solution by manually splitting the content into pages and managing the printing or display logic. Here’s an example of how you can navigate through true pages in a RichTextBox using the HasMorePages approach:

using System.Drawing;
using System.Drawing.Printing;
using System.Windows.Forms;

public partial class Form1 : Form
{
    private RichTextBox richTextBox;
    private PrintDocument printDocument;
    private int currentPage;
    private float yPos;

    public Form1()
    {
        InitializeComponent();

        richTextBox = new RichTextBox();
        richTextBox.Dock = DockStyle.Fill;

        printDocument = new PrintDocument();
        printDocument.PrintPage += PrintDocument_PrintPage;

        currentPage = 1;

        Controls.Add(richTextBox);

        // Call the method to initiate printing or display
        PrintOrDisplayContent();
    }

    private void PrintOrDisplayContent()
    {
        if (printDocument.PrinterSettings.IsValid)
        {
            // Print the content
            printDocument.Print();
        }
        else
        {
            // Display the content in a preview window
            PrintPreviewDialog printPreviewDialog = new PrintPreviewDialog();
            printPreviewDialog.Document = printDocument;
            printPreviewDialog.ShowDialog();
        }
    }

    private void PrintDocument_PrintPage(object sender, PrintPageEventArgs e)
    {
        // Define the print area
        RectangleF printArea = e.MarginBounds;

        // Set the initial vertical position
        yPos = printArea.Top;

        // Calculate the number of lines that fit in the print area
        int linesPerPage = (int)(printArea.Height / richTextBox.Font.GetHeight(e.Graphics));

        // Iterate through the text to split it into pages
        while (currentPage <= richTextBox.Lines.Length)
        {
            // Check if there are more lines to print on this page
            if (linesPerPage > 0)
            {
                // Calculate the remaining height for this page
                float remainingHeight = printArea.Height - (yPos - printArea.Top);

                // Calculate the number of lines that fit in the remaining space
                int linesThatFit = (int)(remainingHeight / richTextBox.Font.GetHeight(e.Graphics));

                // Determine the number of lines to print on this page
                int linesToPrint = Math.Min(linesPerPage, linesThatFit);

                // Print the lines on the page
                for (int i = 0; i < linesToPrint; i++)
                {
                    string line = richTextBox.Lines[currentPage - 1];
                    e.Graphics.DrawString(line, richTextBox.Font, Brushes.Black, printArea.Left, yPos);
                    yPos += richTextBox.Font.GetHeight(e.Graphics);
                    currentPage++;
                }

                // Decrease the number of lines that can be printed on subsequent pages
                linesPerPage -= linesToPrint;

                // Check if there are more lines to print
                if (currentPage <= richTextBox.Lines.Length)
                {
                    // Check if there is enough space for another page
                    if (linesPerPage > 0)
                    {
                        // Specify that there are more pages to print
                        e.HasMorePages = true;
                        return;
                    }
                }
            }
            else
            {
                // Specify that there are more pages to print
                e.HasMorePages = true;
                return;
            }
        }
    }
}

In this example, a RichTextBox control is added to a form