Fixed string length

[Madball]

Hello

I am trying to create a string of text that grabs info from other cells, which is easy so for example

=A1&A2&A3

would grab all the info from the 3 cells and merge them to create a string, but what I want to do is create a prefixed length.

Lets say A1, A2 and A3 would equal 10 characters in total but B1, B2 and B3 would equal 7 characters, these would be different lengths. so for a visual description I would like them to appear like this

At the moment

01MAIN-HELLO
01DESSERT-HELLO WORLD

Would like

01MAINXXX-HELLO
01DESSERT-HELLO WORLD

This would make both strings the same length and would make it easier for me to export to a custom file that needs a certain length prefix.

What formula do I use for that?