How do I find the closest array element to an arbitrary (non-member) number?

Question

Seemingly similar questions: \"Finding closest number in an array\" (in Java) and \"find nearest match to array of doubles\" (actually a geography problem).

Answer 1

List results;
int target = 0;
int nearestValue = 0;
if (results.Any(ab => ab == target)) {
    nearestValue= results.FirstOrDefault(i => i == target);
} else {
    int greaterThanTarget = 0;
    int lessThanTarget = 0;
    if (results.Any(ab => ab > target) {
        greaterThanTarget = results.Where(i => i > target).Min();
    }

    if (results.Any(ab => ab < target)) {
        lessThanTarget = results.Where(i => i < target).Max();
    }

    if (lessThanTarget == 0 ) {
        nearestValue= greaterThanTarget;
    } else if (greaterThanTarget == 0) {
        nearestValue = lessThanTarget;
    } else {
        if (target - lessThanTarget < greaterThanTarget - target) {
            nearestValue = lessThanTarget;
        } else {
            nearestValue = greaterThanTarget;
        }
    }
}