You might want to set a field’s value based on the contents of another field. In this example, we want to multiply the values of two fields only if another field has a certain value.
There are these columns: Owner Text, Number Column, Number 2 and Number 3.
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We want to do a calculation in [[NumberColumn]] such that [[Number2]]*[[Number3]] would only work when [[OwnerText]] is “Demo User2”. We set the validation condition, validation text, and initial value as shown below.
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As per the expressions laid out, the [[Number2]]*[[Number3]] calculation only works for the list item that has Demo User2 under the Owner Text column. The form is not saved for the other two list items (4*8 and 2*8), and the validation text is displayed.
Validation expressions can be applied to many other situations to ensure that forms are only saved when the field inputs meet certain conditions.