React Tutorial

What is React?

React is an open-source front-end JavaScript library that's utilized for building component bassed client application

• React is especially used for Single page application
• It is used for handling View layer of Web Application and Mobile app.
• React Uses JSX syntax. JSX is as syntax extension of JS that allow developers to write HTML in their JS Code
• React uses Virtual Dom instead of Real DOM.
• Real DOM manipulation are expensive.
• React uses reusable UI Components to develop the view.

What is JSX?

JSX stands for JavaScript XML and it is an XML-Like extension to ECMA Script. Basically it provide the syntax for the Below Function.

React.createElement(type, props,... children)

In the below example the text inside <h1> tag is returned as JavaScript function to render function.

export default function App(){
return(
    <h1>{"Hello this is JSX code!"} </h1>
  );
 }

If you don't use JSX syntax then the respective JavaScript code should be written as below.

Functional Component

  import {createElement} from 'react';
  export default function App(){
     return createElement(
      'h1',
      {
     className:'greeting'},
      'Hello, This is a JSx Code'
    );
  }

Class Component

  class App extend React.Component{
     render(){
      return(
     <h1>"{Hello, This is a JSx Code}</h1>
    );
  }
 }

Read cookie using JavaScript Code

Read cookie using JavaScript Code

Today, we'll look at how to use JavaScript code to read cookies. The function readCookie, which is located below, accepts a cookie's name and returns its value.

function readCookie(name) {
  var nameEQ = name + "=";
  var ca = document.cookie.split(';');
  for(var i=0;i < ca.length;i++)
    {
     var c = ca[i];
     while (c.charAt(0)==' ')
     {
      c = c.substring(1,c.length);
     }
    if (c.indexOf(nameEQ) == 0)
     return c.substring(nameEQ.length,c.length);
    }
  return null;
}

I will demonstrate how to generate cookies using JavaScript in the code below.

function cookieCheck(){
  var interval;
  if(readCookie("userlogTime") == null)
  {
   var cDateTime = new Date();
   var timeSet = cDateTime.getHours();
   document.cookie ="userlogTime="+timeSet;
   }
  }
The above code show how we can create cookie using javascript

Deferred in SharePoint JSON

How to use Deferred in SharePoint JSOM?

I'll demonstrate how to utilize Deferred in SharePoint Online today.
All functions in SharePoint operate asynchronously, however occasionally we must call a function after another has finished. Assuming we have two lists and must retrieve data sequentially from each, delayed is used in this scenario