If you want to be a JavaScript programmer, you must know these things.

1. What are the Truthy and Falsy values?

Answer: A truthy value is like true and a falsy value is like false. These are as follows:

So, If we use one of these values in the if-else statement then we will get the same output which is shown below. In this given example, I will show you these values using ternary expression inside the console.log() method.

Examples:

falsy-truthy values

2. What is the difference between null and undefined?

Answer: Firstly, null means an empty or non-existent value. It is supposed to be something that doesn’t exist. …


If you want to be a react developer, you must know these 10 things.

Introduction: React is a Javascript library for building interactive and fast user interfaces or, UI components. It makes it easier to build dynamic web applications. Because it required less coding and offer more functionality. On the other hand, coding mostly gets complex very quickly in javascript.

01. JSX: It means Javascript syntax extension. It’s used to describe that what the user interface should look like. By using JSX, We can write HTML structure in the same file that contains javascript code. It makes the code easier to understand and debug. It sets HTML to javascript code. …


Some advanced JavaScript concepts

If you want to be a JavaScript Developer, you must know these things.

01. Error Handling: Sometimes our codes have errors. These errors happen because of our mistakes, maybe an unexpected input, or for a hundred other reasons. So, we use try…catch to handle these errors.

try…catch: It has two main blocks: try and catch. At first ‘try’ block is executed. If there is no error then the catch(error) is ignored. If there are occurs then the try execution is stopped then catch(error) show an error.

Example:

try…catch block syntax

02. Curly Braces: We should use curly braces in the given method, not use other methods. Because this method is usually more readable.


Some important javascript features

If you want to be a JavaScript programmer, you must know these things.

01. Number: If the value of a variable is expressed by a number, then it is called a number-type variable. If the value cannot be converted then it shows NaN. JavaScript number has many types : isNaN(), parseInt(), parseFloat() etc.

Number.isNaN(): This method for checking if something is not a number and its type is a Number.

Example:

Number.parseInt(): This method converts a string to an integer (a whole number).

Example:

Number.parseFloat(): This method converts a string to a point number.

Example:

02. String: If the value of a variable is expressed with…


If you want to be a JavaScript developer, you must know these 10 things.

1. Template String

The template string is indicated with a dollar sign and curly brackets (${expression}) inside the backtick symbol.

Example:

2. Let and Const

In the Es6 version of JavaScript, variables can be declared in two more ways. The first is that we can declare a variable with the keyword let.

By applying the keyword let we can change the value of the variable more than once. If we use the keyword let in a block scope then we will not access it outside of this block scope.

We can also declare a variable by applying the keyword const. …


If you want to be a JavaScript programmer, you must know these 10 things.

Some important concepts of JavaScript.

1. Variable:

Where data is stored, it is called a variable in JavaScript. To declare a variable, first of all, we have to write the reserved keyword var of JavaScript. Then we have to give a name to the variable. This means what variable it is, whether it is a person, or the thing, etc. Then we have to given an equal sign. Then, we have to write a value, which means any person can have a name, age, height, and name of any object, etc. Then, we have to give a semicolon. Remember, the name of…

Muhammad Shahnewaz

Web Developer

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