Try [1] to see if it makes it a little easier assembling a regex pattern. It can create the pattern as a string or create a RegExp with the pattern already assembled.
RegExPatterns.createRegExp("my search value", RegExPatterns.CONTAINS);
RegExPatterns.createPatternString ("my search value", RegExPatterns.CONTAINS);
[1]
https://flex.apache.org/asdoc/spark/components/supportClasses/RegExPatterns.html
-Mark
