What is the difference between Null vs Undefined?

Ans: Null is an assigned value. It means nothing. Undefined means a variable has been declared but not defined yet.

What is the difference between double(==) vs triple(===)?

Ans: Duble(==) in javascript is used for comparing two variables, but it ignores the…

React js is a library. But it is not a framework. React.js use for creating user interfaces. React is not a complete solution. Though now react is the most popular library to create user interfaces but we need to know to use other libraries.

React DOM

DOM means “Document Object Model”. We use DOM API to change a document, style, and content. Now it is most popular because it created a common language between developers and browsers. React support all popular browsers including internet explorer 9 and above, although some polyfills are required for older browser such as IE 9 and IE 10.

React JSX

React JSX is a react extension which is allows writing javascript code that looks like HTML. To use JSX we need to use capitalized format.The react library must be also always in scope from yourJSX code.

  1. Block bindings occur whenever we declare or set a value in a variable.ES6 offers block bindings using var, let, and const. Example: var = 1; let = 2; const = 3
  2. Global Block Bindings Global scope behavior for var is different than let and const. When we use var in…
  1. String.concat() The concat() method merges two or more arrays. This method does not change the existing arrays but instead returns a new array. example: const fruit1 = [‘banana’]; const fruit2 = [‘mangoes]; const fruit3 = [‘fruit1.concat(fruit2)’]; console.log(fruit3); output: [“banana,mangoes”]
  2. String.includes() The includes() method performs a case-sensitive search to determine whether…

Kamrul Hasan

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