InfoPath Dev

I have a requirement to have a six digit field's unused available spaces filled with dashes.

example1:  wheel-

examle 2:  car---

If six characters are entered, then nothing needs to be done.  I was trying to figure a way to do this by using string-length, then set the fields value by concatinating dashes onto the field's value,but I haven't come up with a way yet.  Any suggestions???

I got it!  I am just going to concat a string of dashes onto the field value and take a substring of that.

Smart solution! So, you'll concat the field with a string of 6 dashes, then use substring to return the first 6 characters.... Thanks for posting your answer, in case someone else comes looking for something like this.

Yep!  The reason for the dashes is that this field is concat'd with additional fields to form an ID, which needs to always be a certain length.