> For the complete documentation index, see [llms.txt](https://docs.helmut.de/helmut4-releases/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.helmut.de/helmut4-releases/v4.9.1/helmut4-components/streamdesigner/nodes/actions/misc/regex-apply-action.md).

# Regex Apply Action

With the help of the Regex Apply Action it is possible to clean a string (for example a project name) via a REGEX. For example, if the permitted characters were restricted to a-A and 0-1 and this REGEX was applied to the string, all characters that do not meet this requirement would be replaced. It is possible to define with which other characters these should be replaced. The conformed string is available via the wildcard {stream.last\_result} or via {node.result.?} And can thus be used in the stream in the corrected form.