<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="TextBox1" ErrorMessage="RegularExpressionValidator" ValidationExpression="\d{5}">Enter 5 digits</asp:RegularExpressionValidator>
 protected void Page_Load(object sender, EventArgs e)
        {
            FpSpread1.NonEditModeValidation = true;
            FarPoint.Web.Spread.TextCellType tcell1 = new FarPoint.Web.Spread.TextCellType();
            tcell1.Validators.Add(RegularExpressionValidator1);
            FpSpread1.ActiveSheetView.Columns[1].CellType = tcell1;
            FpSpread1.ActiveSheetView.Columns[1].BackColor = System.Drawing.Color.AliceBlue;
            FpSpread1.ValidationErrorMessage = "test";
        }
	 
	
		<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="TextBox1" ErrorMessage="RegularExpressionValidator" ValidationExpression="\d{5}">Enter 5 digits</asp:RegularExpressionValidator>
Protected Sub Page_Load(sender As Object, e As System.EventArgs)
            FpSpread1.NonEditModeValidation = True
            Dim tcell1 As New FarPoint.Web.Spread.TextCellType()
            tcell1.Validators.Add(RegularExpressionValidator1)
            FpSpread1.ActiveSheetView.Columns(1).CellType = tcell1
            FpSpread1.ActiveSheetView.Columns(1).BackColor = System.Drawing.Color.AliceBlue
            FpSpread1.ValidationErrorMessage = "test"
End Sub