This Is Why Learning New JavaScript ES6 Syntax Is So Famous!

This Is Why Learning New JavaScript ES6 Syntax Is So Famous!

ECMASCRIPT 2015 or ES6 has introduced many changes to JavaScript. JavaScript ES6 has introduced new syntax and new awesome features to make your code more modern and more readable.

Originally published by Adesh  at zeptobook.com

What is ES6?

ECMASCRIPT 2015 or ES6 has introduced many changes to JavaScript. JavaScript ES6 has introduced new syntax and new awesome features to make your code more modern and more readable.

It allows you to write less code and do more.

ES6 introduced many great features like arrow functions, template strings, class destructions, modules… and many more.

Let’s dive into more reasons of its popularities.

Reason 1: You can write it now for all Browsers.

ES6 is now supported in all major browsers. Here is the list of Browsers support for ES6.

Photo Courtesy: W3Schools.com

Reason 2: Full Backward Browser Compatible

It has support for backward compatible version of JavaScript in current and older browsers or environments. JavaScript being a rich ecosystem, has hundreds of packages on the package manager (NPM), and it has been adopted worldwide. To make sure ES5 JavaScript packages should always work in the presence of ES6, they decided to make it 100% backward compatible.

This has one major benefit. You can start writing ES6 along with your existing JavaScript ES5. This also help you to start slowly embracing new features and adopting the aspects of ES6, which can make your life easier as a programmer.

To support full backward browser compatibility, here is a very cool project called Babel.

What is Babel?

Babel is a JavaScript Transpiler that converts edge JavaScript into plain old ES5 JavaScript that can run in any browser. For more details about Babel, please click the below links.

Learn more about Babel.

Babel Usage Guide. How to setup Babel?

Reason 3: ES6 is faster in some cases.

I am going to share one performance benchmark for ES6. ES6 performed more better or even hit the performance benchmark for the same function written in ES5. You can visit this link as well to check the ES6 performance benchmark.

Performance of ES6 features relative to the ES5 baseline operations per second

Reason 4: Doing more with writing less code

As said above, now you can do lot more with writing less code in your ES6. You can write more cleaner and concise code in ES6. Here is few examples of code syntax of ES6.

1. Arrow Functions in ES6

No need to write function and return keywords anymore. This is one of the more awesome feature of ES6, makes your code looks more readable, more structured, and looks like modern code. You don’t need to write old syntax anymore.

An arrow function expression has a shorter syntax than a function expression and does not have its own this, arguments, super, or new.target.

Arrow Function Body

One of the benefit of arrow function is to have either concise body or the usual block body.

In a concise body, only an expression is mentioned in a single line with the implicit return value. In a block body, you must use explicit return keyword, normally with curly braces { return .. }.

var func = x => x * x;                  
// concise body with implicit return keyword

var func = (x, y) => { return x + y; };
// block body with explicit return keyword

Line Break in Arrow function

ES6 will throw an error if there is an improper line break in arrow function. Ideally, it should be single line statement. If you want to use it as multi line statement, use the proper curly braces or brackets.

var func = (a, b, c)
=> 1;
// Throw syntax error

//Use Proper syntax
var func = (
a,
b,
c
) => (
1
);
// no SyntaxError thrown

Arrow function example in ES6 vs ES5

//ES6
odds = evens.map(v => v + 1)

//ES5
odds = evens.map(function (v) { return v + 1; });

2. Extended Parameter Handling in ES6

2.1 Default Parameter Value

Simple and smart way of passing default values of function parameters. Now, functions can be defined with default parameters values. If you miss to pass the function parameter, then missing or undefined values will be initialized with default parameters.

Prevent you from undefined error

Default parameter will prevent you from getting the undefined error. If you forget to write the parameter, it won’t return the undefined error, because the parameter is already defined in the function parameter.

Default parameter example in ES6 vs ES5

//ES6
function f (a, b = 10, c = 20) {
return x + y + z
}
f(5) === 35

//ES5
function f (a, b, c) {
if (b === undefined)
y = 10;
if (c === undefined)
c = 20;
return x + y + z;
};
f(1) === 35;

2.2 Rest Parameter

Easy way to pass rest parameters with three dots (…) with parameter name. With the help of rest parameter, you can pass an indefinite number of arguments as an array.

A function last parameter prefixed with ... which will cause all remaining arguments to be placed within a standard JavaScript array.

Only a last parameter can be a rest parameter.

Rest parameter are like an Array

One of the major difference between argument object and rest parameter is that, rest parameter are like real array instance, where argument object are not like a real array. This means that, you can apply array methods like sort, map, forEach or pop on it directly.

Rest parameter example in ES6 vs ES5

//ES6
function f (a, b, ...z) {
return (a + b) * z.length
}
f(10, 20, "ZeptoBook", true, 5) === 25

//ES5
function f (a, b) {
var z = Array.prototype.slice.call(arguments, 2);
return (a + b) * z.length;
};
f(10, 20, "ZeptoBook", true, 5) === 25

3. Template Literals in ES6

String Interpolation

Concatenating the string in a more cleaner way. Template literals are string literals, which allow concatenated expression. String interpolation is one of the interesting feature of ES6. Prior to ES6, we use double or single quotes to concatenate string expression, which sometimes looks very weird and buggy.

Now, in ES6, template literals are enclosed by back-ticks () character instead of single or double quotes. You can find back-ticks at the top left of your keyboard under the esc key.

Template literals has placeholders with $ sign and curly braces like ${expression}. $ sign is mandatory for interpolation.

Example of string concatenation in ES6 vs ES5

//ES6
var product = { quantity: 20, name: "Macbook", unitprice: 1000 }
var message = I want to buy ${product.name}, for a total of ${product.unitprice * product.quantity} bucks?

//ES5
var product = { quantity: 20, name: "Macbook", unitprice: 1000 }
var message = "I want to buy " + product.name + ",\n" +
"for a total of " + (product.unitprice * product.quantity) + " bucks?";

4. Enhanced Object Properties in ES6

Property Shorthand

Shorter syntax for defining object properties. Prior to ES6, every object property needs to be either getter-setter or key-value pair. This has been completely changed in ES6. In ES6, there is a concise way for defining the object properties. You can define complex object properties in a much cleaner way now.

//ES6
var x = 0, y = 0
obj = { x, y }

//ES5
var x = 0, y = 0;
obj = { x: x, y: y };

Method Properties

Support for method notation in object properties definitions. In the same way, which we discussed above, we can now define object methods concisely and in a much cleaner way.

//ES6
obj = {
add (a, b) {

},
multi (x, y) {

},

}

//ES5
obj = {
add: function (a, b) {

},
multi: function (x, y) {

},

};

Reason 5: New Built-In Methods In ES6

Object Property Assignment

There is a new function to assign enumerable properties of one or more source objects into a destination object.//ES6
var dest = { quux: 0 }
var src1 = { foo: 1, bar: 2 }
var src2 = { foo: 3, baz: 4 }
Object.assign(dest, src1, src2)
dest.quux === 0
dest.foo === 3
dest.bar === 2
dest.baz === 4

//ES5
var dest = { quux: 0 };
var src1 = { foo: 1, bar: 2 };
var src2 = { foo: 3, baz: 4 };
Object.keys(src1).forEach(function(k) {
dest[k] = src1[k];
});
Object.keys(src2).forEach(function(k) {
dest[k] = src2[k];
});
dest.quux === 0;
dest.foo === 3;
dest.bar === 2;
dest.baz === 4;

Array Element Finding

There is a new function to find an element in an array.

//ES6
[ 10, 30, 40, 20 ].find(x => x > 30) // 40
[ 10, 30, 40, 20 ].findIndex(x => x > 30) // 20

//ES5
[ 10, 30, 40, 20 ].filter(function (x) { return x > 30; })[0]; // 40
// no such function in ES5

String Repeating

There is a new string repeating functionality as well.

//ES6
" ".repeat(5 * depth)
"bar".repeat(3)

//ES5
Array((5 * depth) + 1).join(" ");
Array(3 + 1).join("bar");

String Searching

New string functions to search for a sub-string

//ES6
"zepto".startsWith("epto", 1) // true
"zepto".endsWith("zept", 4) // true
"zepto".includes("zep") // true
"zepto".includes("zep", 1) // true
"zepto".includes("zep", 2) // false

//ES5
"zepto".indexOf("epto") === 1; // true
"zepto".indexOf("zept") === (4 - "zept".length); // true
"zepto".indexOf("ept") !== -1; // true
"zepto".indexOf("ept", 1) !== -1; // true
"zepto".indexOf("ept", 2) !== -1; // false

Number Type Checking

There are new functions for checking non-numbers and finite numbers.

//ES6
Number.isNaN(50) === false
Number.isNaN(NaN) === true

Number.isFinite(Infinity) === false
Number.isFinite(-Infinity) === false
Number.isFinite(NaN) === false
Number.isFinite(50) === true

//ES5
var isNaN = function (n) {
return n !== n;
};
var isFinite = function (v) {
return (typeof v === "number" && !isNaN(v) && v !== Infinity && v !== -Infinity);
};
isNaN(50) === false;
isNaN(NaN) === true;

isFinite(Infinity) === false;
isFinite(-Infinity) === false;
isFinite(NaN) === false;
isFinite(50) === true;

Number Safety Checking

There is an in-built function to check whether an integer number is in the safe range.

//ES6
Number.isSafeInteger(50) === true
Number.isSafeInteger(1208976886688) === false

//ES5
function isSafeInteger (n) {
return (
typeof n === 'number'
&& Math.round(n) === n
&& -(Math.pow(2, 53) - 1) <= n
&& n <= (Math.pow(2, 53) - 1)
);
}
isSafeInteger(50) === true;
isSafeInteger(1208976886688) === false;

Number Truncation

There is a mathematical function to truncate a floating number to its integral parts, completely dropping the fractional part.

//ES6
console.log(Math.trunc(12.7)) // 12
console.log(Math.trunc(0.4)) // 0
console.log(Math.trunc(-0.4)) // -0

//ES5
function mathTrunc (x) {
return (x < 0 ? Math.ceil(x) : Math.floor(x));
}
console.log(mathTrunc(12.7)) // 12
console.log(mathTrunc(0.4)) // 0
console.log(mathTrunc(-0.4)) // -0

Summary

Javascript surely isn’t a perfect language. It has various imperfections. In the course of recent years, developers have gotten increasingly more involvement with the JavaScript ES5, which has lead to enhancements. ES6 brings many engrossing features that were not seen in previous version like ES5.


Originally published by Adesh  at zeptobook.com

===========================================

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JavaScript Tutorial: if-else Statement in JavaScript

JavaScript Tutorial: if-else Statement in JavaScript

This JavaScript tutorial is a step by step guide on JavaScript If Else Statements. Learn how to use If Else in javascript and also JavaScript If Else Statements. if-else Statement in JavaScript. JavaScript's conditional statements: if; if-else; nested-if; if-else-if. These statements allow you to control the flow of your program's execution based upon conditions known only during run time.

Decision Making in programming is similar to decision making in real life. In programming also we face some situations where we want a certain block of code to be executed when some condition is fulfilled.
A programming language uses control statements to control the flow of execution of the program based on certain conditions. These are used to cause the flow of execution to advance and branch based on changes to the state of a program.

JavaScript’s conditional statements:

  • if
  • if-else
  • nested-if
  • if-else-if

These statements allow you to control the flow of your program’s execution based upon conditions known only during run time.

  • if: if statement is the most simple decision making statement. It is used to decide whether a certain statement or block of statements will be executed or not i.e if a certain condition is true then a block of statement is executed otherwise not.
    Syntax:
if(condition) 
{
   // Statements to execute if
   // condition is true
}

Here, condition after evaluation will be either true or false. if statement accepts boolean values – if the value is true then it will execute the block of statements under it.
If we do not provide the curly braces ‘{‘ and ‘}’ after if( condition ) then by default if statement will consider the immediate one statement to be inside its block. For example,

if(condition)
   statement1;
   statement2;

// Here if the condition is true, if block 
// will consider only statement1 to be inside 
// its block.

Flow chart:

Example:

<script type = "text/javaScript"> 

// JavaScript program to illustrate If statement 

var i = 10; 

if (i > 15) 
document.write("10 is less than 15"); 

// This statement will be executed 
// as if considers one statement by default 
document.write("I am Not in if"); 

< /script> 

Output:

I am Not in if
  • if-else: The if statement alone tells us that if a condition is true it will execute a block of statements and if the condition is false it won’t. But what if we want to do something else if the condition is false. Here comes the else statement. We can use the else statement with if statement to execute a block of code when the condition is false.
    Syntax:
if (condition)
{
    // Executes this block if
    // condition is true
}
else
{
    // Executes this block if
    // condition is false
}


Example:

<script type = "text/javaScript"> 

// JavaScript program to illustrate If-else statement 

var i = 10; 

if (i < 15) 
document.write("10 is less than 15"); 
else
document.write("I am Not in if"); 

< /script> 

Output:

i is smaller than 15
  • nested-if A nested if is an if statement that is the target of another if or else. Nested if statements means an if statement inside an if statement. Yes, JavaScript allows us to nest if statements within if statements. i.e, we can place an if statement inside another if statement.
    Syntax:
if (condition1) 
{
   // Executes when condition1 is true
   if (condition2) 
   {
      // Executes when condition2 is true
   }
}

Example:

<script type = "text/javaScript"> 

// JavaScript program to illustrate nested-if statement 

var i = 10; 

if (i == 10) { 

// First if statement 
if (i < 15) 
	document.write("i is smaller than 15"); 

// Nested - if statement 
// Will only be executed if statement above 
// it is true 
if (i < 12) 
	document.write("i is smaller than 12 too"); 
else
	document.write("i is greater than 15"); 
} 
< /script> 

Output:

i is smaller than 15
i is smaller than 12 too
  • if-else-if ladder Here, a user can decide among multiple options.The if statements are executed from the top down. As soon as one of the conditions controlling the if is true, the statement associated with that if is executed, and the rest of the ladder is bypassed. If none of the conditions is true, then the final else statement will be executed.
if (condition)
    statement;
else if (condition)
    statement;
.
.
else
    statement;


Example:

<script type = "text/javaScript"> 
// JavaScript program to illustrate nested-if statement 

var i = 20; 

if (i == 10) 
document.wrte("i is 10"); 
else if (i == 15) 
document.wrte("i is 15"); 
else if (i == 20) 
document.wrte("i is 20"); 
else
document.wrte("i is not present"); 
< /script> 

Output:

i is 20

How to Retrieve full Profile of LinkedIn User using Javascript

How to Retrieve full Profile of LinkedIn User using Javascript

I am trying to retrieve the full profile (especially job history and educational qualifications) of a linkedin user via the Javascript (Fetch LinkedIn Data Using JavaScript)

Here we are fetching LinkedIn data like Username, Email and other fields using JavaScript SDK.

Here we have 2 workarounds.

  1. Configuration of linkedIn developer api
  2. Javascript Code to fetch records

Configuration of linkedIn developer api

In order to fetch records, first we need to create developer api in linkedin which will act as token/identity while fetching data from other linkedin accounts.

So to create api, navigate to https://linkedin.com/developer/apps and click on 'Create Application'.

After navigating, fill in details like name, description and other required fields and then submit.

As we submit, it will create Client ID and Client Secret shown below, which we will be using in our code while communicating to fetch records from other LinkedIn account.

Note: We need to provide localhost Url here under Oauth 2.0. I am using my localhost, but you can probably use other production URLs under Oauth 2.0 where your app is configured. It will make your api  consider the Url as trusted which fetching records.

Javascript Code to fetch records

For getting user details like first name, last name,User image can be written as,

<script type="text/javascript" src="https://platform.linkedin.com/in.js">  
    api_key: XXXXXXX //Client ID  
    onLoad: OnLinkedInFrameworkLoad //Method that will be called on page load  
    authorize: true  
</script>  
<script type="text/javascript">  
    function OnLinkedInFrameworkLoad() {  
        IN.Event.on(IN, "auth", OnLinkedInAuth);  
    }  
  
    function OnLinkedInAuth() {  
        IN.API.Profile("me").result(ShowProfileData);  
    }  
  
    function ShowProfileData(profiles) {  
        var member = profiles.values[0];  
        var id = member.id;  
        var firstName = member.firstName;  
        var lastName = member.lastName;  
        var photo = member.pictureUrl;  
        var headline = member.headline;  
        //use information captured above  
        var stringToBind = "<p>First Name: " + firstName + " <p/><p> Last Name: " + lastName + "<p/><p>User ID: " + id + " and Head Line Provided: " + headline + "<p/>"  
        document.getElementById('profiles').innerHTML = stringToBind;  
    }  
</script>    

Kindly note we need to include 'https://platform.linkedin.com/in.js' as src under script type as it will act on this Javascript SDK provided by Linkedin.

In the same way we can also fetch records of any organization with the companyid as keyword.

<head>  
    <script type="text/javascript" src="https://platform.linkedin.com/in.js">  
        api_key: XXXXXXX ////Client ID  
        onLoad: onLinkedInLoad  
        authorize: true  
    </script>  
</head>  
  
<body>  
    <div id="displayUpdates"></div>  
    <script type="text/javascript">  
        function onLinkedInLoad() {  
            IN.Event.on(IN, "auth", onLinkedInAuth);  
            console.log("On auth");  
        }  
  
        function onLinkedInAuth() {  
            var cpnyID = XXXXX; //the Company ID for which we want updates  
            IN.API.Raw("/companies/" + cpnyID + "/updates?event-type=status-update&start=0&count=10&format=json").result(displayCompanyUpdates);  
            console.log("After auth");  
        }  
  
        function displayCompanyUpdates(result) {  
            var div = document.getElementById("displayUpdates");  
            var el = "<ul>";  
            var resValues = result.values;  
            for (var i in resValues) {  
                var share = resValues[i].updateContent.companyStatusUpdate.share;  
                var isContent = share.content;  
                var isTitled = isContent,  
                    isLinked = isContent,  
                    isDescription = isContent,  
                    isThumbnail = isContent,  
                    isComment = isContent;  
                if (isTitled) {  
                    var title = isContent.title;  
                } else {  
                    var title = "News headline";  
                }  
                var comment = share.comment;  
                if (isLinked) {  
                    var link = isContent.shortenedUrl;  
                } else {  
                    var link = "#";  
                }  
                if (isDescription) {  
                    var description = isContent.description;  
                } else {  
                    var description = "No description";  
                }  
                /* 
                if (isThumbnailz) { 
                var thumbnailUrl = isContent.thumbnailUrl; 
                } else { 
                var thumbnailUrl = "http://placehold.it/60x60"; 
                } 
                */  
                if (share) {  
                    var content = "<a target='_blank' href=" + link + ">" + comment + "</a><br>";  
                    //el += "<li><img src='" + thumbnailUrl + "' alt=''>" + content + "</li>";  
                    el += "<li><div>" + content + "</div></li>";  
                }  
                console.log(share);  
            }  
            el += "</ul>";  
            document.getElementById("displayUpdates").innerHTML = el;  
        }  
    </script>  
</body>  

We can get multiple metadata while fetching records for any any organization. We can get company updates as shown below.

Conclusion

We can also fetch any company specific data like company job updates/post, total likes, comments, and number of views along with a lot of metadata we can fetch which I have shown below.

Thank you for reading !

7 Best Javascript Iframe Libraries

7 Best Javascript Iframe Libraries

Iframes let you build user experiences into embeddable ‘cross-domain components’, which let users interact with other sites without being redirected. I have compiled 7 best Javascript iframe libraries.

Iframes let you build user experiences into embeddable ‘cross-domain components’, which let users interact with other sites without being redirected. I have compiled 7 best Javascript iframe libraries.

1. Zoid

A cross-domain component toolkit, supporting:

  • Render an iframe or popup on a different domain, and pass down props, including objects and functions
  • Call callbacks natively from the child window without worrying about post-messaging or cross-domain restrictions
  • Create and expose components to share functionality from your site to others!
  • Render your component directly as a React, Vue or Angular component!
    It's 'data-down, actions up' style components, but 100% cross-domain using iframes and popups!

Download


2. Postmate

Postmate is a promise-based API built on postMessage. It allows a parent page to speak with a child iFrame across origins with minimal effort.

Download


3. Iframe Resizer

Keep same and cross domain iFrames sized to their content with support for window/content resizing, in page links, nesting and multiple iFrames

Demo

Download


4. Iframely

Embed proxy. Supports over 1800 domains via custom parsers, oEmbed, Twitter Cards and Open Graph

Demo

Download


5. React Frame component

This component allows you to encapsulate your entire React application or per component in an iFrame.

Demo

Download


6. Seamless.js

A seamless iframe makes it so that visitors are unable to distinguish between content within the iframe and content beside the iframe. Seamless.js is a JavaScript library (with no dependencies) that makes working with iframes easy by doing all the seamless stuff for you automatically.

Demo

Download


7. Porthole

A proxy to safely communicate to cross-domain iframes in javascript

Demo

Download


Thank for read!