Page 119 - JavaScript

can use array's reduce function like below:

var columns = ["Date", "Number", "Size", "Location", "Age"];
var rows = ["2001", "5", "Big", "Sydney", "25"];
var result = rows.reduce(function(result, field, index) {
result[columns[index]] = field;
return result;
}, {})

console.log(result);

Output:

{
Date: "2001",
Number: "5",
Size: "Big",
Location: "Sydney",
Age: "25"
}

Convert a String to an Array

The .split() method splits a string into an array of substrings. By default .split() will break the
string into substrings on spaces (" "), which is equivalent to calling .split(" ").

The parameter passed to .split() specifies the character, or the regular expression, to use for
splitting the string.

To split a string into an array call .split with an empty string (""). Important Note: This only works
if all of your characters fit in the Unicode lower range characters, which covers most English and
most European languages. For languages that require 3 and 4 byte unicode characters, slice("")
will separate them.

var strArray = "StackOverflow".split("");
// strArray = ["S", "t", "a", "c", "k", "O", "v", "e", "r", "f", "l", "o", "w"]

6

Using the spread operator (...), to convert a string into an array.

var strArray = [..."sky is blue"];
// strArray = ["s", "k", "y", " ", "i", "s", " ", "b", "l", "u", "e"]

Test all array items for equality

The .every method tests if all array elements pass a provided predicate test.

To test all objects for equality, you can use the following code snippets.

[1, 2, 1].every(function(item, i, list) { return item === list[0]; }); // false

https://riptutorial.com/ 76