InfoPath Dev

Hi,

I would like to limit the user to only making one selection on a Multiple Selection List Box. I know I could use a drop down list box - But I like the format of the MSLB because it has the check boxes. Plus my MSLB is connected to a secondary data source and filtered by a previous field selection. The MSLB resizes and formats beautifully and really adds to the users experience. Trouble is - I only want the end user to be able to make a single selection.

Is there xpath or rules I can use to do this? One more thing - I'm using a sharepoint list form.

Thank you in advance!

 Add a rule to the selection box. The condition is number of occurrences of field1 > 1. Tick the box Disable this control.

Thanks Wilkies. That put me in the right direction - I didnt know about that formatting rule.

Doing "Number of occurences of field1 > 1" - disabled the control perfectly. However a clear button to set field1 to blank did not re-enable the control (maybe blank is still an occurence?)

So I changed it to "Any occurence of field1 is not blank - disable control". Then a clear button (set field1 = "") re-enabled the control.

Thanks Again!