Remove Last 3 Characters Of String Or Number In Javascript

In JavaScript, manipulating strings and numbers is a common task for many developers. One specific operation that you may find yourself needing to do is to remove the last three characters of a string or number. This can be useful in various scenarios, such as data processing or formatting output.

To remove the last three characters of a string in JavaScript, you can use the `slice` method. This method extracts a section of a string and returns a new string without modifying the original one. Here's how you can use it to remove the last three characters:

const originalString = "Hello, World!";
const modifiedString = originalString.slice(0, -3);
console.log(modifiedString); // Output: Hello, Wo

In the example above, we first define the original string as "Hello, World!". By calling `slice(0, -3)` on the `originalString`, we effectively remove the last three characters from it and store the result in `modifiedString`.

Similarly, when dealing with a number instead of a string, you can convert the number to a string first and then proceed with the same approach as shown above. Here's an example:

const originalNumber = 123456789;
const modifiedNumberString = originalNumber.toString().slice(0, -3);
const modifiedNumber = Number(modifiedNumberString);
console.log(modifiedNumber); // Output: 123456

In this case, we convert the `originalNumber` to a string using `toString()`, remove the last three characters with `slice(0, -3)`, and then convert the resulting string back to a number using `Number()` to get the modified number.

Furthermore, if you wish to create a reusable function to remove the last `n` characters from a string, you can define a function like this:

function removeLastNCharacters(str, n) {
    return str.slice(0, -n);
}

const original = "JavaScript is awesome!";
const modified = removeLastNCharacters(original, 5);
console.log(modified); // Output: JavaScript is

By using the `removeLastNCharacters` function, you can easily remove any specified number of characters from the end of a string without repeating the slice operation multiple times.

In conclusion, manipulating strings and numbers in JavaScript, including removing the last three characters, can be achieved efficiently using the `slice` method. By mastering this simple technique, you can enhance your coding skills and handle various data processing tasks with ease.