We have an input field, into which the user must type a value but only certain characters are allowed. The allowed characters are:
- A-Z (any case)
- the numbers 0-9
- the $ character
- the minus character
- the underscore character
If a user enters invalid characters a tooltip appears which currently states:
The ID may only contain the characters: A-Z, a-z, 0-9, $, -, _
Feedback from our tester states that he finds the commas confusing as he thinks that the error message states that a comma should be allowed! The developer thinks that the lack of commas in the error message makes it confusing.
Is there a standard way to display this sort of information? Can anyone advise?
Note: This is for an English website.