我需要将当前URL中的查询字符串传递给GPT（Google Publisher Tag），以便在页面加载时调用DFP。例如，如果这是URL：
http://example.net/article/100-days.html?c=xyz
我需要将c=xyz插入为键值。我有50多组这些c=查询字符串，并且需要GPT调用针对出现的任何字符串（无论是c=xyz还是c=abc等）的广告。
<head>
<script type="text/javascript">
var googletag = googletag || {};
googletag.cmd = googletag.cmd || [];
(function() {
var gads = document.createElement("script");
gads.async = true;
gads.type = "text/javascript";
var useSSL = "https:" == document.location.protocol;
gads.src = (useSSL ? "https:" : "http:") + "//www.googletagservices.com/tag/js/gpt.js";
var node =document.getElementsByTagName("script")[0];
node.parentNode.insertBefore(gads, node);
})();
</script>
<script type="text/javascript">
googletag.cmd.push(function() {
googletag.defineSlot('/6355419/Travel/Europe/France/Paris',[300, 250], "banner1"); // adds the first slot with it's own slot level custom targeting
googletag.pubads().setTargeting("c","xyz"); // adds custom targeting that applies to the entire page - i.e. all the slots on the page.
googletag.enableServices();
});
</script>
</head>
我认为这需要一个获取函数，但我不确定在JS中最有效的方法是什么。