codice:
<%
filmato = "<object width=""480"" height=""385""><param name=""movie"" value=""http://www.youtube.com/v/GjNZKxP5LEI?fs=1&hl=it_IT""></param><param name=""allowFullScreen"" value=""true""></param><param name=""allowscriptaccess"" value=""always""></param><embed src=""http://www.youtube.com/v/GjNZKxP5LEI?fs=1&hl=it_IT"" type=""application/x-shockwave-flash"" allowscriptaccess=""always"" allowfullscreen=""true"" width=""480"" height=""385""></embed></object>"
Set RegX = NEW RegExp
Dim MyString, SearchPattern, ReplacedText
MyString = filmato
SearchPattern = "width=""\d*"""
ReplaceString = "width=""200"""
RegX.Pattern = SearchPattern
RegX.Global = True
intermedia = RegX.Replace(MyString, ReplaceString)
MyString = intermedia
SearchPattern = "height=""\d*"""
ReplaceString = "height=""200"""
RegX.Pattern = SearchPattern
RegX.Global = True
ReplacedText = RegX.Replace(MyString, ReplaceString)
response.write replacedtext
%>
E' un pochino prolisso per fini didattici, la puoi semplificare/adattare e creare una apposita funzione
ciao