How to count the number of elements that match a condition with LINQ

Question

I\'ve tried a lot of things but the most logical one for me seems this one:

int divisor = AllMyControls.Take(p => p.IsActiveUserControlChecked).Count();
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Answer 1

The parameter for Take requres an int and you are passing in a delegate/ lambda expression. Take is designed to just take the first count of the elements.

You can use the Count method and pass in a delegate to count the elements that fit its criteria. This way you only iterate the IEnumerable once, rather than first culling out the ones that don't fit your criteria, and then again to actually count them.

AllMyControls.Count(p => p.IsActiveUserControlChecked);