By using brackets in format strings in field definitions, field profiles, and identifiers, you can limit which characters are valid in field values.
This topic does not apply when writing format strings in field specifications
This specification... |
...means this |
N[1357] |
One digit: 1, 3, 5, or 7. |
N[1357](3) |
Three digits, each of which can be 1, 3, 5, or 7. |
X[#]N[4] |
A "#" character and then 4. |
X[AaBb] |
One character: A, a, B, or b. |
An exclusion symbol, "^", is available to disallow invalid characters. In order to disallow characters, the "^" symbol must be in the first position of the string. All characters following the "^" are disallowed.
This specification... |
...means this |
A[^QVZ] |
Any letter of the alphabet except Q, V, or Z. |
N[^135] |
Any digit except 1, 3, or 5 |
X[^*](2-4) |
Two to four characters; not an asterisk. |
If the "^" is not at the beginning of the string, then "^" is a valid character.
This specification... |
...means this |
X[#<^] |
One of three possible characters: "#", "<", or "^". |
X[#<^135] |
One of six possible characters: "#", "<", "^", 1, 3, or 5. |
X[#<^^] |
An invalid specification. |