How to make a JavaScript number from a line

'Convert strings to numbers in JavaScript using parseInt() & parseFloat(), illustrated with an example.'

Creating a JavaScript Number

JavaScript allows us to create numbers in a number of ways. In this example, we will look at how to create a number from a line. To do this, we will use the Number() function.

// Create a number from a line
let lineNumber = Number("12345");

// Print the result
console.log(lineNumber);

The Number() function takes a string as an argument and returns the number represented by that string. In this case, it returns the number 12345. It is important to note that the Number() function only works with numbers and will throw an error if the string provided is not a valid number.

You can also use the parseInt() function to parse a string and return an integer. This function is often used when dealing with strings that contain numbers, as it allows you to extract the number from the string and convert it to an integer. For example:

// Create an integer from a line
let lineInteger = parseInt("12345");

// Print the result
console.log(lineInteger);

The parseInt() function takes a string and returns the integer that is represented by that string. In this case, it returns the integer 12345. It is important to note that the parseInt() function only works with integers and will throw an error if the string provided is not a valid integer.

Finally, you can also use the parseFloat() function to parse a string and return a floating-point number. This function is often used when dealing with strings that contain numbers, as it allows you to extract the number from the string and convert it to a floating-point number. For example:

// Create a float from a line
let lineFloat = parseFloat("12345.67");

// Print the result
console.log(lineFloat);

The parseFloat() function takes a string and returns the floating-point number that is represented by that string. In this case, it returns the number 12345.67. It is important to note that the parseFloat() function only works with floating-point numbers and will throw an error if the string provided is not a valid floating-point number.

In summary, there are a number of ways to create a number from a line in JavaScript. The Number(), parseInt(), and parseFloat() functions are all useful for this purpose.