Using Shorthand Conditional Expressions

In addition to the if statement, JavaScript provides a shorthand type of conditional expression that you can use to make quick decisions. This uses a peculiar syntax that is also found in other languages, such as C. A conditional expression looks like this:

variable = (condition) ? (true action) : (false action);

This assigns one of two values to the variable: one if the condition is true, and another if it is false. Here is an example of a conditional expression:

value = (a == 1) ? 1 : 0;

This statement might look confusing, but it is equivalent to the following if statement:

if (a == 1) {
   value = 1;
} else {
   value = 0;
}

In other words, the value after the question mark (?) will be used if the condition is true, and the value after the colon (:) will be used if the condition is false. The colon represents the else portion of this statement and, like the else portion of the if statement, is optional.