public event CustomDrawRowHeaderEventHandler CustomDrawRowHeader

Public Event CustomDrawRowHeader As CustomDrawRowHeaderEventHandler

using System;
using System.Drawing;
using DevExpress.Spreadsheet;
using DevExpress.XtraSpreadsheet;
// ...
private void spreadsheetControl1_CustomDrawRowHeader(object sender, CustomDrawRowHeaderEventArgs e)
{
    // Cancel default painting for the row header.
    e.Handled = true;

    // Display a row number for every fifth row.
    if ((e.RowIndex + 1) % 5 == 0)
    {
        // Specify font style.
        e.Appearance.FontStyleDelta = FontStyle.Bold;

        // Return the row header bounds.
        Rectangle textBounds = e.Bounds;

        // Specify row header text.
        string text = (e.RowIndex + 1).ToString();

        // Specify text alignment. 
        StringFormat format = new StringFormat {
            LineAlignment = StringAlignment.Center,
            Alignment = StringAlignment.Center
        };

        // Draw row header text.
        e.Graphics.DrawString(text, e.Font, 
            e.Cache.GetSolidBrush(Color.FromArgb(91, 155, 213)), textBounds, format);
    }
}

Imports System
Imports System.Drawing
Imports DevExpress.Spreadsheet
Imports DevExpress.XtraSpreadsheet
' ...
Private Sub spreadsheetControl1_CustomDrawRowHeader(ByVal sender As Object,
    ByVal e As CustomDrawRowHeaderEventArgs)
    ' Cancel default painting for the row header.
    e.Handled = True

    ' Display a row number for every fifth row.
    If (e.RowIndex + 1) Mod 5 = 0 Then
        ' Specify font style.
        e.Appearance.FontStyleDelta = FontStyle.Bold

        ' Return the row header bounds.
        Dim textBounds As Rectangle = e.Bounds

        ' Specify row header text.
        Dim text As String = (e.RowIndex + 1).ToString()

        ' Specify text alignment. 
        Dim format As New StringFormat With {
            .LineAlignment = StringAlignment.Center,
            .Alignment = StringAlignment.Center
        }

        ' Draw row header text.
        e.Graphics.DrawString(text, e.Font,
    e.Cache.GetSolidBrush(Color.FromArgb(91, 155, 213)), textBounds, format)
    End If
End Sub

AddHandler spreadsheetControl1.CustomDrawColumnHeaderBackground, AddressOf spreadsheetControl1_CustomDrawColumnHeaderBackground
AddHandler spreadsheetControl1.CustomDrawRowHeader, AddressOf spreadsheetControl1_CustomDrawRowHeader
AddHandler spreadsheetControl1.CustomDrawRowHeaderBackground, AddressOf spreadsheetControl1_CustomDrawRowHeaderBackground