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Found 6710 Articles for Javascript

17K+ Views
In this article, the given task is to get the best way of finding the length of a JSON object in JavaScript. Input-Output Scenario Let’s look into this input-output scenario. Consider there is an object with some keys and values in it. we need to get the length of the object. const MyObj = { Name: "Mike", Age: 34 }; document.write(Object.keys(MyObj).length); // Output: 2 Using Object.keys() The Object.keys() method will return the output in form of array of a given object’s own enumerable properties names. It will return the output of keys ... Read More

7K+ Views
A JSON (JavaScript object notation) Object is always surrounded by the curly braces {}. The values must be a valid JSON data type, and the keys must be strings. JSON supports the following data types: number, string, object, Boolean, array, and null. There has to be a colon (":") separating the keys and values. A comma separates each key and value pair. Following is the syntax of JSON Object − JSONObject = {} Following is the basic declaration of JSON Object in JavaScript − JSONObject = { "name" : "Suriya", ... Read More

101 Views
Suppose, we have an array and objects like these −Objects:const main = [ {name: "Karan", age: 34}, {name: "Aayush", age: 24}, {name: "Ameesh", age: 23}, {name: "Joy", age: 33}, {name: "Siddarth", age: 43}, {name: "Nakul", age: 31}, {name: "Anmol", age: 21}, ];Array:const names = ["Karan", "Joy", "Siddarth", "Ameesh"];We are required to write a JavaScript function that takes in two such arrays and filters the first array in place to contain only those objects whose name property is included in the second array.Therefore, let’s write the code for this function −ExampleThe code for this ... Read More

5K+ Views
Given two arrays and the task is to convert those two arrays into a JSON object. Where the first array elements are keys of the object and the second array elements are values of the object. Input-Output Scenario Let’s look into the scenario of how two arrays will be converted into a JSON object. Consider two arrays are having some elements. Now, we need to convert these two arrays into a JSON object. Array1 = [1, 2, 3, 4]; Array2 = ['A', 'B', 'C', 'D']; Output = {"1":"A", "2":"B", "3":"C", "4":"D"} //JSON object In this article, ... Read More

407 Views
We are required to write a JavaScript function that takes in a string that represents a number.Replace the leading zero with spaces in the number. Make sure the prior spaces in number are retained.For example: If the string value is defined as −"004590808"Then the output should come as −"4590808"ExampleThe code for this will be −const str = ' 004590808'; const replaceWithSpace = str => { let replaced = ''; const regex = new RegExp(/^\s*0+/); replaced = str.replace(regex, el => { const { length } = el; return ' '.repeat(length); }); return replaced; }; console.log(replaceWithSpace(str));OutputThe output in the console will be −4590808

4K+ Views
We are required to write a JavaScript function that takes in a number and calculates its square root without using the Math.sqrt() function.Therefore, let’s write the code for this function −ExampleThe code for this will be −const square = (n, i, j) => { let mid = (i + j) / 2; let mul = mid * mid; if ((mul === n) || (Math.abs(mul - n) < 0.00001)){ return mid; }else if (mul < n){ return square(n, mid, j); }else{ return square(n, i, mid); } ... Read More

786 Views
We are required to write a JavaScript function that takes in a string. It should print out each number for every corresponding letter in the string.For example:a = 1 b = 2 c = 3 d = 4 e =5 . . . y = 25 z = 25Note: Remove any special characters and spaces.So, if the input is −"hello man"Then the output should be −"8, 5, 12, 12, 15, 13, 1, 14"ExampleThe code for this will be −const str = 'hello man'; const charPosition = str => { str = str.split(''); const arr = []; const ... Read More

13K+ Views
Given there is a number with digits after decimal point and the task is to find the count of digits after the decimal point. Input Output Scenario Let’s look into the input output scenario, where there is a floating point number having some digits after decimal point. Input = 45.36346323 Output = 8 As we can in the above snippet there are 8 digits in the floating point number after the decimal point. To achieve the above task, we used three methods. Namely isInteger(), toString() and, split() method. Let’s see them one by one – Number.isInteger()method The ... Read More

143 Views
We are required to write a JavaScript function that takes in an array of numbers and returns a number which can exactly divide all the numbers in the array.Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr = [4, 6, 34, 76, 78, 44, 34, 26, 88, 76, 42]; const dividesAll = el => { const result = []; let num; for (num = Math.floor(el / 2); num > 1; num--){ if (el % num === 0) { result.push(num); } }; return result; }; const dividesArray = arr => { return arr.map(dividesAll).reduce((acc, val) => { return acc.filter(el => val.includes(el)); }); }; console.log(dividesArray(arr));OutputThe output in the console will be −[ 2 ]

7K+ Views
We are required to write a JavaScript function that takes in an array of numbers.The function should sort the array using the Array.prototype.sort() method, but, here, we are required to use the Array.prototype.reduce() method to sort the array.Therefore, let’s write the code for this function −ExampleThe code for this will be −const arr = [4, 56, 5, 3, 34, 37, 89, 57, 98]; const sortWithReduce = arr => { return arr.reduce((acc, val) => { let ind = 0; while(ind < arr.length && val < arr[ind]){ ind++; } acc.splice(ind, 0, val); return acc; }, []); }; console.log(sortWithReduce(arr));OutputThe output in the console will be −[ 98, 57, 89, 37, 34, 5, 56, 4, 3 ]