More Complex Conditions

Let's take a look at how we can create more complex logical conditions in programming. We can use the logical "AND" (&&), logical "OR" (||), logical negation (!) and brackets (()).

Logical "AND", "OR" and "NOT"

This is a short example that demonstrates the power of logical "AND", logical "OR" and logical "NOT":

var animal = "horse";
int speed = 45;

if ((animal == "horse" || animal == "donkey") && (speed > 40))
    Console.WriteLine("Run fast")
else if ((animal == "shark" || animal == "dolphin") && (speed > 45))
    Console.WriteLine("Swim fast")
else if (!(speed > 30 || animal == "turtle"))
    Console.WriteLine("Slow move")

We shall explain the logical AND (||), the logical OR (||), and the logical NOT (!) in the next few sections, along with examples and exercises:

• Logical "AND"
• Logical "OR"
• Logical "NOT"

The Parenthesis () Operator

Like the rest of the operators in programming, the operators && and || have a priority, as in the case && is with higher priority than ||. The operator () serves for changing the priority of operators and is being calculated first, just like in mathematics. Using parentheses also gives the code better readability and is considered a good practice.

Example of checking whether a variable belongs to certain ranges:

if (x < 0) || ((x >= 5) && (x <= 10)) || (x > 20)
{
    ...
}