function storeData(name, value){
	if(value === null){
		sessionStorage.removeItem(name);
	}else{
		sessionStorage.setItem(name, value);
	}
}

function storeData(name, value, opt){
	if(value === null){
		sessionStorage.removeItem(name);
	}else{
		sessionStorage.setItem(name, value);
	}
}

function getStoreData(name){
	var value = sessionStorage.getItem(name);
	if(value == 'null'){
		return null;
	}else{
		return value;
	}
}