function OpenBrWindow(theURL,winName,features, myWidth, myHeight, isCenter) { //v3.0
  if(window.screen)if(isCenter)if(isCenter=="true"){
    var myLeft = (screen.width-myWidth)/2;
    var myTop = (screen.height-myHeight)/2;
    features+=(features!='')?',':'';
    features+=',left='+myLeft+',top='+myTop;
  }
 oOpenWindow=  window.open(theURL,winName,features+((features!='')?',':'')+'width='+myWidth+',height='+myHeight);
 
 oOpenWindow.focus();
}

function CenterDiv(id, heig, widt){
	obj = document.getElementsByTagName("div");
	obj[id].style.left = (screen.width-widt)/2;
	obj[id].style.top = (screen.height-heig)/2;
}

function CenterDivs(){
	CenterDiv('Letter',600,450);
	CenterDiv('Subscription',600,450);
}

function ShowHide(id, visibility) {
	obj = document.getElementsByTagName("div");
	obj[id].style.visibility = visibility;
}

function SendSurvey(sId, aId){
	OpenBrWindow("SendSurvey.aspx?sID=" + sId + "&aId=" + aId,"Anketa","toolbar=no,location=no,status=no,menubar=no,scrollbars=no,resizable=no","420","100","true")
}

function OpenSurveys(){
	OpenBrWindow("SurveyArchive.aspx","Anketa","toolbar=no,location=no,status=no,menubar=no,scrollbars=yes,resizable=no","320","500","true")
}