JavaScript arrays can hold multiple data values of the same or different types, and can be indexed by number or word. They are like a box of books, with each book representing a data value. The length of an array can be dynamic, and associative arrays are useful for working with properties of the document object. Arrays are often used with for loops to iterate through elements for various purposes.
An array in JavaScript® is a special type of variable that can hold multiple pieces of information or data values and is a place of storage in memory. These data values can be of the same type or of different types, but having different data types in an array in JavaScript® is unusual. It’s generally easier to figure out what these arrays are by comparing them to something as simple as a box of books. The box is the equivalent of the array, and the books that the box contains represent multiple data values.
In this example, each book is information known as a data value. Books can be different types of books and can contain very different content. This kind of flexibility with an array in JavaScript® is not present in so-called strongly typed programming languages like Java or C++. JavaScript® is a programming language, but it’s often referred to as a scripting language because it’s often used by web developers to code client-side scripts or small programs as opposed to full software applications. An array in JavaScript® allows the programmer to access a specific element in the invisible container variable, since elements or data values are indexed by a number or word.
If a magic marker was used to write a unique number starting from zero on each of the books in the box, a specific number that refers to only one book could be used to retrieve that book without retrieving all the other books in the array. This characteristic of an array in JavaScript® is known as indexing the particular data value. Could be thought of as the name of the object. Data values in an array are counted from zero; counting is the assignment of an index for organizational purposes. The count starts at zero, not one, so the first element to be added to a new array is indexed to zero, the second element is indexed to one, and the addition of subsequent elements follows this pattern.
Programmers in this language have the freedom to simply add an element wherever they want because the length of an array in JavaScript® can be dynamic, which is not allowed in strongly typed programming languages. When elements are indexed by a word instead of a number, it is called an associative array in JavaScript®. Associative arrays are useful when working with arrays that are also properties of the document object. An array in JavaScript® is often used with what is known as a “for loop” due to how often web developers have to iterate through all the elements in the variable for various purposes.
For example, a programmer may need to print all capital cities of European countries for the desired functionality of a script. He or she could use a for loop to loop, one by one, through each of the capital names of various countries in Europe that are contained in the array and identified by their index so that, as they are “called,” they are Street. The use of an array in JavaScript® is determined by the purpose of the script. Not all scripts, especially very small ones, need to contain an array in their code.
Protect your devices with Threat Protection by NordVPN
