Master page was printed

Hi everybody,
I have a javascript to control a page named "Blank" to display in my form .The "Blank" page is not included in page Numbering. Here is the java code:

var myCount = xfa.layout.pageCount();
if(myCount%4 > 0){
this._Blank.setInstances(4-(myCount%4));
var myPages = this.resolveNodes("Blank[*]");
for(var q=0; q<myPages.length; q++){
  myPages.item(q).presence = "visible";
}
}else{
this._Blank.setInstances(0);
}

When I open the pdf , the page number is 17,so the Blank page needs to dispay (3 pages). It works functionally.
When I print the pdf , there are some hidden pages need to display(3 pages). So the Blank page do not needs to display. But now the pdf adds a extra blank page in my form . I test it is the Blank's Master Page .

Can someone help me?

Thanks a lot .
Jing