Thanks Henry. Actually "v1.0" going to change dynamically. Actually I'm going to get array of file names with different version info. But I don't know what is the version, I know only first three strings, "appName", "siteName" and "featureName".
This version can be anything like v2.0, v3.0 or even version1,version2
so can we say [a-z|0-9|.] for this version part?
I'm sure that this version will have only alpha, numeric and "." (dot).
but its not working i'm not getting true.