get to post google map gdownloadurl

this is the javascript.

var url = "http://google.com/gmap.jsp?uid="+userid+"&lat="+lat;
GDownloadUrl(url,function(doc){}); 

how to change from get开发者_StackOverflow社区 to post? any idea? thanks

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i think this it

GDownloadUrl("http://google.com/gmap.jsp",function(doc){},"uid="+userid+"&lat="+lat");