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10 Lesser-Known JavaScript Tricks

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autumn
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2 min read

In this article, I have outlined 10 great JavaScript tricks to help you make the most of its capabilities. Whether you're just starting to learn or already deep into practice, I believe you can learn something new from these. So, let's dive in now.

1.Scroll to Top Method

You can use the scrollTo() method to scroll to a specific position on the page.

window.scrollTo({
 top: 0, 
 behavior: "smooth",
});

2.Double Tilde for Math.floor

Using double tilde (~~) is a quick way to perform the Math.floor operation.

let num = 5.67;
let rounded = ~~num;

3.Convert Strings to Numbers without parseInt

The plus operator (+) can be used to convert strings to numbers.

let str = "42";
let num = +str;

4.Optional Chaining Operator (?.)

The optional chaining operator (?.) allows handling potentially undefined properties.

let user = {
 address: {
  street: "123 Main St"
 }
};
let street = user?.address?.street;

5.Logical OR Operator for Setting Default Values

Use the logical OR operator (||) to set default values for your applications.

let name = getUsername() || "Guest";

6.Object.entries for Iterating Object Properties

Object.entries returns an array of [key, value] pairs of its own enumerable properties.

let person = { name: "John", age: 30};

for(let [key, value] of Object.entries(person)){
 console.log(`${key}: ${value}`);
}

7.Counting <h1> Tags on a Page

This will print the count of <h1> tags on the page.

console.log(document.getElementsByTagName('h1'));

8.Variable Swapping without Temporary Variables

An example of swapping values of a and b without using a temporary variable.

let a = 5, b = 10;
[a, b] = [b, a];

9.Creating Arrays with Array.from

Array.from can be used to create arrays in a concise way.

let array = Array.from({length: 5}, (_, index) => index + 1);

10.Checking for NaN

NaN is the only value in JavaScript that is not equal to itself.

let value = "Not a Number";

if(value !== value){
 console.log("NaN");
}

Conclusion

These are the 10 JavaScript tricks I wanted to share with you today. I hope you can learn something new from them, helping you enhance your productivity and enjoy a better life.

Learn more:

JavaScript