Public Overloads Sub SetConditionalFormatting( _
   ByVal row As Integer, _
   ByVal column As Integer, _
   ByVal rowCount As Integer, _
   ByVal columnCount As Integer, _
   ByVal ParamArray rules() As IConditionalFormattingRule _
) 

Dim instance As SheetView
Dim row As Integer
Dim column As Integer
Dim rowCount As Integer
Dim columnCount As Integer
Dim rules() As IConditionalFormattingRule
 
instance.SetConditionalFormatting(row, column, rowCount, columnCount, rules)

public void SetConditionalFormatting( 
   int row,
   int column,
   int rowCount,
   int columnCount,
   params IConditionalFormattingRule[] rules
)

protected void Page_Load(object sender, System.EventArgs e)
                       {
                           FpSpread1.Sheets[0].Cells[0, 0].Value = 3;
                           FpSpread1.Sheets[0].Cells[1, 0].Value = 2;
                           FpSpread1.Sheets[0].Cells[1, 1].Value = 10;
                           FpSpread1.Sheets[0].Cells[0, 2].Value = 1;    
                       }

protected void Button1_Click(object sender, EventArgs e)
        {
            //Unique or Duplicate CF
            FarPoint.Web.Spread.UniqueOrDuplicatedConditionalFormattingRule ud = new FarPoint.Web.Spread.UniqueOrDuplicatedConditionalFormattingRule(false);
            ud.IsUnique = true;
            ud.BackColor = Color.Thistle;
            FpSpread1.ActiveSheetView.SetConditionalFormatting(0, 0, 3, 3, ud);
        }

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
            FpSpread1.Sheets(0).Cells(0, 0).Value = 3
            FpSpread1.Sheets(0).Cells(1, 0).Value = 2
            FpSpread1.Sheets(0).Cells(1, 1).Value = 10
            FpSpread1.Sheets(0).Cells(0, 2).Value = 1
        End Sub

Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
             'Unique or Duplicate CF
            Dim ud = New FarPoint.Web.Spread.UniqueOrDuplicatedConditionalFormattingRule(False)
            ud.IsUnique = True
            ud.BackColor = Drawing.Color.Thistle
            FpSpread1.ActiveSheetView.SetConditionalFormatting(0, 0, 3, 3, ud)
        End Sub