Coding interview preparation
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Browser to Virtual DOM.png
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Virtual DOM works in three steps:

1. Whenever any data changes in the React App, the entire UI is re-rendered in Virtual DOM representation.
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Virtual DOM and Real DOM.png
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2. Now, the difference between the previous DOM representation and the new DOM is calculated.
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Real DOM.png
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3. Once the calculations are completed, the real DOM updated with only those things which are changed.
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How React's ES6 syntax is different from ES5 syntax?

1. require vs. Import
// ES5
var React = require('react');

// ES6
import React from 'react';
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2. exports vs. export
// ES5
module.exports = Component;

// ES6
export default Component;
3. component and function
// ES5
var MyComponent = React.createClass({
render: function() {
return(
<h3>Hello JavaTpoint</h3>
);
}
});

// ES6
class MyComponent extends React.Component {
render() {
return(
<h3>Hello Javatpoint</h3>
);
}
}
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4. props
// ES5
var App = React.createClass({
propTypes: { name: React.PropTypes.string },
render: function() {
return(
<h3>Hello, {this.props.name}!</h3>
);
}
});

// ES6
class App extends React.Component {
render() {
return(
<h3>Hello, {this.props.name}!</h3>
);
}
}
Python Quiz
Anonymous Quiz
31%
A
35%
B
17%
C
17%
D
Python Complete Tutorial By Guido Van Rossum and Team.pdf
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Python Complete Tutorial by Guido Van Rossum and Team
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Common Coding Mistakes to Avoid
Even experienced programmers make mistakes.


Undefined variables:

Ensure all variables are declared and initialized before use.

Type coercion:

Be mindful of JavaScript's automatic type conversion, which can lead to unexpected results.

Incorrect scope:

Understand the difference between global and local scope to avoid unintended variable access.

Logical errors:

Carefully review your code for logical inconsistencies that might lead to incorrect output.

Off-by-one errors:

Pay attention to array indices and loop conditions to prevent errors in indexing and iteration.

Infinite loops:

Avoid creating loops that never terminate due to incorrect conditions or missing exit points.

Example:
// Undefined variable error
let result = x + 5; // Assuming x is not declared

// Type coercion error
let age = "30";
let isAdult = age >= 18; // Age will be converted to a number

By being aware of these common pitfalls, you can write more robust and error-free code.

Do you have any specific coding mistakes you've encountered recently?
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🧿  ReactJS Cheat-Sheet

This Post includes a ReactJs cheat sheet to make it easy for our followers to work with Reactjs.
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