Search Results for: javascript string

Being able to concatenate (join) two or more strings together is pretty useful – you may be combining user input for storage in a single database column or doing the reverse – combining data from multiple database columns into a single string for display or output. There are several ways to concatenate strings in Javascript, and we’ll cover these methods below, along with some useful examples. The string.concat() Method The string.concat() method will join any number of strings to a given initial string. Syntax string.concat(string1, string2, string3…) Note that: string is … Read more

Want to make a string all lower case in JavaScript? It’s the toLowerCase() method to the rescue! The toLowerCase() method is part of the string object and has full support in all browsers. In JavaScript, strings can either be a primitive or an object – primitives are the most basic kinds of variables, which are not objects, have no methods, and simply represent the given characters. However, String objects have useful methods for manipulating and measuring the string – like toLowerCase(). By default, JavaScript’s string variables are initialized as primitives – but will be automatically … Read more

In this guide, we explain how to measure the length of a string in JavaScript using the length method. JavaScript is a flexible programming language that runs just about everywhere. You can run JavaScript apps in web browsers, build command-line apps you can run in the terminal, mobile apps can be built using platforms like Cordova, and server processes can be written on platforms like Node.js. Naturally, Linux is the environment of choice for many JavaScript developers and is perfect for learning tools like Node.js … Read more

This article will explain and list JavaScript operators and expressions. JavaScript operators perform a given operation on the provided expressions or values. Common operations include comparisons, arithmetic, and ternary operations. You will use JavaScript operators frequently (even the simplest JavaScript code will use multiple operators!), so it’s worth getting to know them, and their expected behaviour. What are Operators and Operands? Javascript operators perform a given operation, for example addition, subtraction, and other arithmetic, comparisons like greater than/less than, and more complicated operations like ternary/comparison … Read more

This article will explain equality and inequality in the JavaScript Programming language, and provide code examples showing how to check if values are equal in value and type. Checking whether two values are equal can get a bit confusing in JavaScript – there is loose equality and strict equality involving types to consider. Read on to find out how testing for equality and inequality works in JavaScript. What are equality and inequality? In programming, equality is the process of checking whether two values are equal … Read more

This article will quickly explain nested for loops in JavaScript, how they are used with multidimensional arrays, and show some examples. For Loops We’ve already covered for loops – check out our article here. To sum up the article, for loops repeat a block of code for a given number of iterations: for (let i = 0; i <= 3; i++) { console.log(i); // Will output the numbers 0-3 to the console } Above, a for loop is defined that defines an initial variable i that is used to control the loop, sets a … Read more

This article will show you how to filter an array using multiple conditions, to return multiple values. Example code is provided. We’ve already covered filtering arrays in general – this article covers specifically how multiple conditions can be used with the Array.filter() method. The Array.filter() Method The filter() method is available on all arrays in JavaScript. It creates a new array, containing only the items from the original array which passes all conditions in a provided function. filter() Method Syntax The syntax for the array filter() method is as follows: ARRAY.filter(ELEMENT => FUNCTION) Note that: ARRAY is … Read more

This quick tutorial will explain the JavaScript valueOf() Method, what it does, and why you might use it. The JavaScript valueOf() method gets the primitive value of the object it is called from. Usually you will not need to call it, however it does have its use cases. Primitives vs Objects In JavaScript, a value or variable has a type of value. A primitive is a value that is not an object, with no methods or properties, representing only the data that it exists as. JavaScript has 7 primitive data types: string number bigint boolean undefined … Read more

The for…in loop in JavaScript loops over all of the properties in an object. This article will explain why and how to use it. JavaScript Objects JavaScript objects are a kind of variable which store the properties for an item you are representing in your code. For example, you may have a car object, which of which the make, year, model, and colour of a car are it’s properties. Each car object would have it’s own separate list of properties which define that car. JavaScript objects can also be used as hash tables – providing … Read more

JavaScript was built for adding interactivity to web pages. It can interact with and modify on-screen elements, including their HTML attributes – thats what setAttribute() does. Here’s how to use it. What is the HTML DOM? The HTML DOM (Document Object Model) is the interface which JavaScript uses to read from and interact with HTML page elements. It’s a data structure which represents every HTML tag present on the page – everything from the root <html> element that wraps your page to every <div>, <p>, <input>, and <em> – everything on the page is … Read more