Useful Javascript Array and Object Methods

Useful Javascript Array and Object Methods

Useful Javascript Array and Object Methods - Object has many useful built-in methods we can use and access to make working with individual objects straightforward...

Useful Javascript Array and Object Methods - Object has many useful built-in methods we can use and access to make working with individual objects straightforward...

I listened to a great Syntax FM podcast that summarized useful JavaScript array and object methods. These methods help developers write clean and readable code. A lot of these methods reduce the need to reach for utility libraries like Lodash.

All the methods in this article are chainable, meaning they can be used in combination with one another and they also don’t mutate data, which is especially important when working with React. With all these array and object methods you’ll find you never have to reach for a for or while loop ever again.

[.filter()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/filter ".filter()")

Creates a new array based on whether the items of an array pass a certain condition.

Example

Create an array of student ages that meet the legal drinking age.

const studentsAge = [17, 16, 18, 19, 21, 17];
const ableToDrink = studentsAge.filter(age => age > 18); // equal to [19, 21]

[.map()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map ".map()")

Creates a new array by manipulating the values in another array. Great for data manipulation and it is often used in React because it is an immutable method.

Example

Create an array that adds a $ to the beginning of each number.

const numbers = [2, 3, 4, 5];
const dollars = numbers.map(number => '$' + number); // equal to ['$2', '$3', '$4', '$5']

[.reduce()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce ".reduce()")

This often overlooked method uses an accumulator to reduce all items in an array to a single value. Great for calculating totals. The returned value can be of any type (i.e. object, array, string, integer).

Example

Add up the integers in an array.

const numbers = [5, 10, 15];
const total = numbers.reduce((accumulator, currentValue) => accumulator + currentValue); // total will be equal to 30

There are some really cool use cases for .reduce() outlined in the MDN docs that provide examples on how to do things likes flattening an array of arrays, grouping objects by a property, and removing duplicate items in array.

[.forEach()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach ".forEach()")

Applies a function on each item in an array.

Example

Log each array item to the console

const emotions = ['happy', 'sad', 'angry'];
emotions.forEach(emotion => console.log(emotion));

// Will log the following:
// 'happy'
// 'sad'
// 'angry'

[.some()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/some ".some()")

Checks if any item in an array passes the condition. A good use case would be checking for user privileges. It can also be used similarly to a .forEach() where you would perform an action on each array item and break out of the loop once a truthy value is returned.

Example

Check if there is at least one 'admin' in an array.

const userPrivileges = ['user', 'user', 'user', 'admin'];
const containsAdmin = userPrivileges.some(element => element === 'admin'); // containsAdmin will be equal to true

[.every()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/every ".every()")

Similar to .some(), but checks if all items in an array pass a condition.

Example

Check if all ratings are equal to or greater than 3 stars.

const ratings = [3, 5, 4, 3, 5];
const goodOverallRating = ratings.every(rating => rating >= 3); // goodOverallRating will be equal to true

[.includes()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/includes ".includes()")

Checks if an array contains a certain value. It’s similar to .some(),but instead of looking for a condition to pass, it looks if the array contains a specific value.

Example

Check if the array includes an item with the string ‘waldo’.

const names = ['sophie', 'george', 'waldo', 'stephen', 'henry'];
const includesWaldo = names.includes('waldo'); // includesWaldo will be equal to true

[Array.from()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/from "Array.from()")

This is a static method that creates an array based on another array or string. You can also pass a map callback function as an argument to further shape the data in the new array. Honestly, I’m not too sure why someone would use this over the .map() method.

Example

Create an array from a string.

const newArray = Array.from('hello'); // newArray will be equal to ['h', 'e', 'l', 'l', 'o']

Create an array that has double the value for each item in another array.

const doubledValues = Array.from([2, 4, 6], number => number * 2); // doubleValues will be equal to [4, 8, 12]

[Object.values()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/values "Object.values()")

Return an array of the values of an object.

Example

const icecreamColors = { chocolate: 'brown', vanilla: 'white', strawberry: 'red' };
const colors = Object.values(icecreamColors); // colors will be equal to ["brown", "white", "red"]

[Object.keys()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys "Object.keys()")

Return an array of the keys of an object.

Example

const icecreamColors = { chocolate: 'brown', vanilla: 'white', strawberry: 'red' };
const types = Object.keys(icecreamColors); // types will be equal to ["chocolate", "vanilla", "strawberry"]

[Object.entries()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/entries "Object.entries()")

Creates an array which contains arrays of key/value pairs of an object.

Example

const weather = { rain: 0, temperature: 24, humidity: 33 };
const entries = Object.entries(weather);
// entries will be equal to
// [['rain', 0], ['temperature', 24], ['humidity', 33]]

Array Spread

Spreading arrays using the spread operator () allows you to expand the elements in an array. It’s useful when concatenating a bunch of arrays together. It’s also a good way to avoid using the splice() method when looking to remove certain elements from an array because it can be combined with the slice() method to prevent direct mutation of an array.

Example

Combine two arrays.

const spreadableOne = [1, 2, 3, 4];
const spreadableTwo = [5, 6, 7, 8];
const combined = [...spreadableOne, ...spreadableTwo]; // combined will be equal to [1, 2, 3, 4, 5, 6, 7, 8]

Remove an array element without mutating the original array.

const animals = ['squirrel', 'bear', 'deer', 'salmon', 'rat'];
const mammals = [...animals.slice(0, 3), ...animals.slice(4)]; // mammals will be equal to ['squirrel', 'bear', 'deer', 'rat']

Object Spread

Spreading an object allows for the addition of new properties and values to an object without mutations (i.e. a new object is created) and it can also be used to combine multiple objects together. It should be noted that spreading objects does not do nested copying.

Example

Add a new object property and value without mutating the original object.

const spreadableObject = { name: 'Robert', phone: 'iPhone' };
const newObject = { ...spreadableObject, carModel: 'Volkswagen' };
// newObject will be equal to
// { carModel: 'Volkswagen', name: 'Robert', phone: 'iPhone' }

Function Rest

Functions can use the rest parameter syntax to accept any number of arguments as an array.

Example

Display the array of passed arguments.

function displayArgumentsArray(...theArguments) {
    console.log(theArguments);
}
displayArgumentsArray('hi', 'there', 'bud'); // Will print ['hi', 'there', 'bud']

[Object.freeze()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/freeze "Object.freeze()")

Prevents you from modifying existing object properties or adding new properties and values to an object. It’s often what people think const does, however const allows you to modify an object.

Example

Freeze an object to prevent the name property from being changed.

const frozenObject = { name: 'Robert' };
Object.freeze(frozenObject);
frozenObject.name = 'Henry'; // frozenObject will be equal to { name: 'Robert' }

[Object.seal()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/seal "Object.seal()")

Stops any new properties from being added to an object, but still allows for existing properties to be changed.

Example

Seal an object to prevent the wearsWatch property from being added.

const sealedObject = { name: 'Robert' };
Object.seal(sealedObject);
sealedObject.name = 'Bob';
sealedObject.wearsWatch = true; // sealedObject will be equal to { name: 'Bob' }

[Object.assign()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/assign "Object.assign()")

Allows for objects to be combined together. This method is not really needed because you can use the object spread syntax instead. Like the object spread operator, Object.assign() does not do deep cloning. Lodash is your best friend when it comes to deep cloning objects.

Example

Combine two objects into one.

const firstObject = { firstName: 'Robert' };
const secondObject = { lastName: 'Cooper' };
const combinedObject = Object.assign(firstObject, secondObject); // combinedObje

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!