Question

Which built-in JavaScript function is used to convert a value to an integer ?

• A. parseFloat()
• B. alert()
• C. isNaN()
• D. parseInt()

Hint:

Always include the radix parameter when calling parseInt() (like parseInt(value, 10)) to ensure your strings are parsed reliably using the base-10 numbering system across different browsers.

Answer 1

The Correct Option is D

Step 1: Explaining Built-in JavaScript Utility Functions:
JavaScript has global built-in functions to convert data types and check values:

Step 2: Evaluating the Options:

• (A) parseFloat(): Parses a string argument and returns a floating-point (decimal) number. For example, parseFloat("3.14") returns 3.14.
• (B) alert(): Displays a pop-up alert dialog box on the screen with a specified message.
• (C) isNaN(): Determines whether a passed value is NaN (Not-a-Number).
• (D) parseInt(): Parses a string argument and extracts an integer value. For example, parseInt("3.14") returns the integer 3. It also accepts a second argument (radix) to specify the mathematical base (e.g., base 10, binary base 2, hexadecimal base 16). Thus, parseInt() (D) is the correct built-in function to convert values to integers.