# How can I convert a string to a number in JavaScript?Antek Nconst t="undefined"!=typeof HTMLImageElement&&"loading"in HTMLImageElement.prototype;if(t){const t=document.querySelectorAll("img[data-main-image]");for(let e of t){e.dataset.src&&(e.setAttribute("src",e.dataset.src),e.removeAttribute("data-src")),e.dataset.srcset&&(e.setAttribute("srcset",e.dataset.srcset),e.removeAttribute("data-srcset"));const t=e.parentNode.querySelectorAll("source[data-srcset]");for(let e of t)e.setAttribute("srcset",e.dataset.srcset),e.removeAttribute("data-srcset");e.complete&&(e.style.opacity=1,e.parentNode.parentNode.querySelector("[data-placeholder-image]").style.opacity=0)}}

In JavaScript, there are multiple ways to convert a string to a number. Let's explore some common approaches: 1. parseInt() or parseFloat() functions: The`parseInt()` function is used to convert a string into an integer (whole number), while the`parseFloat()` 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
``````

The`parseInt()` function parses the string until it encounters a non-numeric character, while`parseFloat()` 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 return`NaN` (Not a Number) if the string cannot be converted into a valid number. 2. Number() function: JavaScript provides a built-in`Number()` 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:

``````1
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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
``````

The`Number()` function automatically handles both integer and floating-point conversions. It also returns`NaN` 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:

``````1
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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 the`Number()` function. However, it may also return`NaN` 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.