JavaScript Ternary Operator

The ternary operator in JavaScript is a shorthand way of writing conditional statements. It is also known as the conditional operator and is represented by the ? and : symbols.

Basic Syntax

The basic syntax for using the ternary operator is:

        
            condition ? expression1 : expression2;
        
    

In this example, the condition is evaluated. If the condition is true, the first expression is executed; otherwise, the second expression is executed.

Simple Examples

Here are some simple examples of using the ternary operator in JavaScript.

        
            const age = 18;
const isAdult = (age >= 18) ? "Adult" : "Minor";
console.log(isAdult); // Output: Adult
        
    

This example demonstrates how to use the ternary operator to check if a person is an adult based on their age.

        
            const x = 10;
const y = (x > 5) ? 100 : 200;
console.log(y); // Output: 100
        
    

This example shows how to use the ternary operator to assign a value based on a condition.

Nesting Ternary Operators

Ternary operators can be nested to handle multiple conditions. However, it is recommended to avoid excessive nesting for readability.

        
            const score = 85;
const grade = (score >= 90) ? 'A' :
              (score >= 80) ? 'B' :
              (score >= 70) ? 'C' :
              (score >= 60) ? 'D' : 'F';
console.log(grade); // Output: B
        
    

This example demonstrates how to classify a student's grade based on their score using nested ternary operators.

Using Ternary Operator for Function Returns

The ternary operator can be used to return different values from a function based on a condition.

        
            function checkNumber(num) {
    return (num >= 0) ? "Positive" : "Negative";
}
console.log(checkNumber(5)); // Output: Positive
console.log(checkNumber(-3)); // Output: Negative
        
    

This example shows how to use the ternary operator to return "Positive" or "Negative" based on the input number.

Important Notes

Here are some important notes and best practices when using the ternary operator in JavaScript:

• The ternary operator is useful for simple conditional assignments or expressions, but for more complex logic, it's better to use regular if-else statements for readability.
• Excessive nesting of ternary operators can make the code hard to read and maintain. Use with caution.
• It's a good practice to use parentheses to clarify the precedence of operations when using ternary operators with other operators.

Summary

The ternary operator provides a concise way to write conditional statements in JavaScript. By understanding its syntax and usage, you can write more efficient and readable code.