Limit to Number of Selections in Multi-Select Text Field

You could make a formula field to count the number of selections and abort the Sav e in a form rule if more that 3. 

var text value = ToText([Combined Text Floor ID]);

Count(
Trim(Part($value,1,";"))<>"",
Trim(Part($value,2,";"))<>"",
Trim(Part($value,3,";"))<>"",
Trim(Part($value,4,";"))<>"",
Trim(Part($value,5,";"))<>"",
Trim(Part($value,6,";"))<>"",
Trim(Part($value,7,";"))<>"",
Trim(Part($value,8,";"))<>"",
Trim(Part($value,9,";"))<>"",
Trim(Part($value,10,";"))<>"",
Trim(Part($value,11,";"))<>"",
Trim(Part($value,12,";"))<>"",
Trim(Part($value,13,";"))<>"",
Trim(Part($value,14,";"))<>"",
Trim(Part($value,15,";"))<>"",
Trim(Part($value,16,";"))<>"",
Trim(Part($value,17,";"))<>"",
Trim(Part($value,18,";"))<>"",
Trim(Part($value,19,";"))<>"",
Trim(Part($value,20,";"))<>"",
Trim(Part($value,21,";"))<>"",
Trim(Part($value,22,";"))<>"",
Trim(Part($value,23,";"))<>"",
Trim(Part($value,24,";"))<>"",
Trim(Part($value,25,";"))<>"")


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Mark Shnier (YQC)
Quick Base Solution Provider
Your Quick Base Coach
http://QuickBaseCoach.com
mark.shnier@gmail.com
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