how to change a string ,such as add a number after some letters

While regsub would technically work, it's going to induce a lot of overhead. There are lots of other ways to go about that: scan, string map, etc.

 

 

Also, if you're looking at maintaining a list of origin -> modified domains, then you might be better of creating a data group to store them in and just do the translation in the code, rather than building out a complex regsub or the like.

 

 

Colin