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Suppose, we have an array of objects like this −const arr = [ {id: 1, name: "Mohan"}, {id: 2, name: "Sohan"}, {id: 3, name: "Rohan"} ];We are required to write a function that takes one such array and constructs an object from it with the id property as key and name as valueThe output for the above array should be −const output = {1:{name:"Mohan"}, 2:{name:"Sohan"}, 3:{name:"Rohan"}}ExampleFollowing is the code −const arr = [ {id: 1, name: "Mohan"}, {id: 2, name: "Sohan"}, {id: 3, name: "Rohan"} ]; const arrayToObject = arr => { const ... Read More
We can select an option from the dropdown list with Selenium webdriver. The Select class is used to handle static dropdown. A dropdown is identified with the tag in an html code.Let us consider the below html code for tag.We have to import org.openqa.selenium.support.ui.Select to work with methods under Select class in our code. Let us see some of the Select methods−selectByVisibleText(arg) – An option is selected if the text visible on the dropdown is the same as the parameter arg passed as an argument to the method.Syntaxsel = Select (driver.findElement(By.id ("option")));sel.selectByVisibleText ("Selenium");selectByValue(arg) – An option is selected ... Read More
Suppose, we have an array of objects like this −const arr = [ {'ID-01':1}, {'ID-02':3}, {'ID-01':3}, {'ID-02':5} ];We are required to add the values for all these objects together that have identical keysTherefore, for this array, the output should be −const output = [{'ID-01':4}, {'ID-02':8}];We will loop over the array, check for existing objects with the same keys, if they are there, we add value to it otherwise we push new objects to the array.ExampleFollowing is the code −const arr = [ {'ID-01':1}, {'ID-02':3}, {'ID-01':3}, {'ID-02':5} ]; const indexOf = function(key){ ... Read More
IntroductionJust as the include statement, include_once also transfers and evaluates script written in one file in another, the difference in two lies in the fact that include_once prevents same file from reloading if already done. As the name indicates, a file will be included only once even if one tries to issue include instruction again.The include_once statement is typically used to set up global variables, enable libraries or any such activity that is expected to be done in the beginning of execution of application.Other than this, behaviour of include_once statement is similar to include statement.include_once ExampleIn following example testscript.php is ... Read More
Suppose we have an array like this −const arr = [ {unit: 35, brand: 'CENTURY'}, {unit: 35, brand: 'BADGER'}, {unit: 25, brand: 'CENTURY'}, {unit: 15, brand: 'CENTURY'}, {unit: 25, brand: 'XEGAR'} ];We are required to write a function that groups all the brand properties of objects whose unit property is the same.Like for the above array, the new array should be −const output = [ {unit: 35, brand: 'CENTURY, BADGER'}, {unit: 25, brand: 'CENTURY, XEGAR'}, {unit: 15, brand: 'CENTURY'} ];We will loop over the array, search for the object with unit value ... Read More
We are required to write a JavaScript function that takes in an array of String / Number literals and returns a subarray of all the elements that were palindrome in the original array.For example −If the input array is −const arr = ['carecar', 1344, 12321, 'did', 'cannot'];Then the output should be −const output = [12321, 'did'];We will create a helper function that takes in a number or a string and checks if it’s a boolean or not. Then we will loop over the array, filter the palindrome elements and return the filtered arrayExampleFollowing is the code −const arr = ['carecar', ... Read More
Suppose, we have an object like this −const products = { "Pineapple":38, "Apple":110, "Pear":109 };All the keys are unique in themselves and all the values are unique in themselves. We are required to write a function that accepts a value and returns its keyFor example: findKey(110) should return −"Apple"We will approach this problem by first reverse mapping the values to keys and then simply using object notations to find their values.ExampleFollowing is the code −const products = { "Pineapple":38, "Apple":110, "Pear":109 }; const findKey = (obj, val) => { const res = {}; ... Read More
We are required to write a JavaScript function that takes in a string and any number of characters specified as separators. Our function should return a splitted array of the string based on all the separators specified.For example −If the string is −const str = 'rttt.trt/trfd/trtr, tr';And the separators are −const sep = ['/', '.', ', '];Then the output should be −const output = [ 'rttt', 'trt', 'trfd', 'trtr' ];ExampleFollowing is the code −const str = 'rttt.trt/trfd/trtr, tr'; const splitMultiple = (str, ...separator) => { const res = []; let start = 0; for(let i = 0; ... Read More
We are required to write a function that, given a number, say, 123, will output an array −[100,20,3]Basically, the function is expected to return an array that contains the place value of all the digits present in the number taken as an argument by the function.We can solve this problem by using a recursive approach.ExampleFollowing is the code −const num = 123; const placeValue = (num, res = [], factor = 1) => { if(num){ const val = (num % 10) * factor; res.unshift(val); return placeValue(Math.floor(num / 10), res, factor * 10); }; return res; }; console.log(placeValue(num));OutputThis will produce the following output in console −[ 100, 20, 3 ]
Suppose we have an array of arrays of numbers like this −const arr = [[1, 45], [1, 34], [1, 49], [2, 34], [4, 78], [2, 67], [4, 65]];Each subarray is bound to contain strictly two elements. We are required to write a function that constructs a new array where all second elements of the subarrays that have similar first value are grouped together.Therefore, for the array above, the output should look like −const output = [ [45, 34, 49], [34, 67], [78, 65] ];We can make use of the Array.prototype.reduce() method that takes help of a Map() ... Read More