What does “with” do in JavaScript?

Question

I saw JavaScript code which begins with with. That\'s a bit confusing. What does it do and how can it be used correctly?

with (sObj) return opti         


        

Answer 1

I would recommend NOT using this because of performance issues, but what the above means is:

for the object sObj (here presumably a select element), all children and properties referenced on this one (or between following curly braces) treat that as their parent scope.