Dynamic Dom

Dynamic Dom

Hi I'm trying to do the following in JavaScript, which is not possible. 
Is it possible in jQuery?

function post_value() {
var oRows = opener.document.getElementById('tbProudctListView').getElementsByTagName('tr');
var iRowCount = oRows.length;
var result = iRowCount - 2;

opener.document.aspnetForm.ctl00_BreadText_ProductsListView_ctrl + result +_txtProductBillede.value = document.form1.txtFilNavnParent.value;
self.close();
}

It does not like when i concatenate the url.