How can I convert a string to a number in JavaScript?
Antek N

In JavaScript, there are multiple ways to convert a string to a number. Let's explore some common approaches: 1. parseInt() or parseFloat() functions: TheparseInt() function is used to convert a string into an integer (whole number), while theparseFloat() function is used to convert a string into a floating-point number (decimal number). Here's an example:

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   var stringNumber = '42';
   var number = parseInt(stringNumber);
   console.log(number); // Output: 42

   var stringFloat = '3.14';
   var floatNumber = parseFloat(stringFloat);
   console.log(floatNumber); // Output: 3.14

TheparseInt() function parses the string until it encounters a non-numeric character, whileparseFloat() parses the string until it reaches the first non-numeric character or the decimal point (in the case of floating-point numbers). It's important to note that both functions may returnNaN (Not a Number) if the string cannot be converted into a valid number. 2. Number() function: JavaScript provides a built-inNumber() function that can be used to convert a string to a number, regardless of whether it's an integer or a floating-point number. Here's an example:

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   var stringNumber = '42';
   var number = Number(stringNumber);
   console.log(number); // Output: 42

   var stringFloat = '3.14';
   var floatNumber = Number(stringFloat);
   console.log(floatNumber); // Output: 3.14

TheNumber() function automatically handles both integer and floating-point conversions. It also returnsNaN if the string cannot be converted into a valid number. 3. Unary plus operator: Another concise way to convert a string to a number is by using the unary plus operator (+). When applied to a string, it attempts to convert it to a numeric value. Here's an example:

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   var stringNumber = '42';
   var number = +stringNumber;
   console.log(number); // Output: 42

   var stringFloat = '3.14';
   var floatNumber = +stringFloat;
   console.log(floatNumber); // Output: 3.14

The unary plus operator is a shorthand method for converting strings to numbers, and it works similarly to theNumber() function. However, it may also returnNaN if the string is not a valid number. These are some common approaches to convert a string to a number in JavaScript. Choose the method that best suits your coding style and requirements. Remember to handle cases where the string may not be a valid number to avoid unexpected results.

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