Example: the format string ''*.xls; *.xlsx'' will allow allow selection of Excel files on the client for this property.
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For a [[#Text|text/string property]], a format string can be used to limit the number of characters client users are allowed to enter.
* To specify a lower bound, use e.g. <code>Length[10]</code> which requires a text input of at least 10 characters;
* To specify a lower bound and an upper bound, use e.g. <code>Length[10;20]</code> which requires a text input of 10 to 20 characters.
{{Hint|<code>Length[0;X]</code> should be used when you only want to specify an upper bound since there's always a lower bound of 0. Note: <code>X</code> has to be an actual number, it doesn't work as a wildcard. For example, <code>Length[10;X]</code> doesn't mean a length greater than 10. Instead, the entire format string will be considered invalid and ignored.}}
[[Category:UBIK Object|MetaProperty]]