In JavaScript, which function is used to parse a string and return an integer?

The function used to parse a string and return an integer in JavaScript is parseInt(). This function reads the string from left to right, converting characters to their numeric values until it encounters a character that is not a valid digit. At that point, it stops reading and returns the integer value that has been parsed up to that point.

For example, if the input string is "123abc", parseInt() will return the integer 123. It also allows for an optional second argument to specify the base of the numeral system to be used, which adds flexibility in parsing different numerical formats.

In contrast, Number() is used to convert a value to a number, which can result in a floating-point number rather than an integer. parseFloat() specifically converts a string to a floating-point number, making it unsuitable for retrieving just integers. The toInteger() function does not exist in the standard JavaScript API, so it would not be a valid choice for parsing integers.