If I have a mask of 9#.999, I can not enter just 1.5. When I press 1. I get a beep. I can enter 01 and then the period is inserted automatically and I can then type 5.
How can I allow for entry of 1 or 2 digits, then a period, then up to 3 optional digits?
Not an expert, but have a suggestion to you. Do a if …else with two different masks. Read the Len before that.
The mask is set in the GUI designer. My understanding was that 9 is an optional number, # is a required number and . is a literal period. I do not see why multiple masks are required?
Is this a bug then? I’ll create a case, I am just not sure if I am using it wrong or not.
Try “#9.999” 
If you use 9#.999, the first digit you enter maches the leftmost 9. Then Xojo expects as next input a required number ("#") - so you can not just enter “.”
But if you use “#9.999”, the first input matches the “#”, then the second digit can be omitted and the “.” can be entered.
[quote=14397:@Jürgen Kurowski]Try “#9.999”
If you use 9#.999, the first digit you enter maches the leftmost 9. Then Xojo expects as next input a required number ("#") - so you can not just enter “.”
But if you use “#9.999”, the first input matches the “#”, then the second digit can be omitted and the “.” can be entered.[/quote]
That indeed did the trick. Didn’t think about how it all matched but your explanation makes it clear, thanks!