Disabling a Format Mask in Forms

[Quoted] Hello, is there any way to programically disable a format mask in an item at run-time? I only want to use the format mask when certain conditions are met on the form. If you don't know the answer to that one then maybe you might know how to compare the contents of an item against a format mask in a when-validate-item trigger. Either solution would work for me, but I would prefer discovering how to change the format mask at runtime.

Thank you for your effort in advance,

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Mark Cudmore
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