spread.options.highlightInvalidData = true;
var dv = GC.Spread.Sheets.DataValidation.createDateValidator(GC.Spread.Sheets.ConditionalFormatting.ComparisonOperators.between, new Date(2012, 11, 31), new Date(2013, 11, 31));
dv.showInputMessage(true);
dv.inputMessage("Enter a date between 12/31/2012 and 12/31/2013.");
dv.inputTitle("Tip");
var style = new GC.Spread.Sheets.Style();
style.validator = dv;
activeSheet.setStyle(1,1,style,GC.Spread.Sheets.SheetArea.viewport);