JavaScript(JS) JS format numbers as currency strings

In JavaScript, you can format numbers as currency strings using the toLocaleString() method. This method takes two optional parameters: the locale and an object with formatting options.

Here's an example of formatting a number as a currency string with the US dollar symbol:

const number = 123456.789;

const currencyString = number.toLocaleString('en-US', {style: 'currency', currency: 'USD'});

console.log(currencyString); // $123,456.79

In the above example, we define a number 123456.789. We then use the toLocaleString() method with the en-US locale and an object with style: 'currency' and currency: 'USD' options to format the number as a currency string with the US dollar symbol. The resulting currency string is $123,456.79.

You can also specify other formatting options such as the number of decimal places, the currency symbol placement, and the grouping separator. Here's an example of formatting a number as a currency string with the euro symbol and two decimal places:

const number = 123456.789;

const currencyString = number.toLocaleString('en-GB', {style: 'currency', currency: 'EUR', minimumFractionDigits: 2, maximumFractionDigits: 2});

console.log(currencyString); // €123,456.79

In this example, we use the en-GB locale and specify minimumFractionDigits: 2 and maximumFractionDigits: 2 to display the number with two decimal places. The resulting currency string is €123,456.79.