...
Additional Note: (FrankZimper) When testing an ASP.NET 2.0 site I had to add an additional leading underscore to the id fields in the regexes. Is the number of underscores dependent on the version of ASP.NET?
Additional Note: (EmmanuelGuyot) What about the cases where VIEWSTATE is split into different part ? The field VIEWSTATEFIELDCOUNT is easy, but as _''_VIEWSTATExx fields number varies, is it possible to set a dynamic NAME in the Request ?