Dictionary TypeScript

'querySelector' is a method in TypeScript and JavaScript that allows you to select elements from an HTML page based on a CSS selector. It is primarily used to interact with the Document Object Model (DOM) and manipulate HTML elements. Here's a detailed explanation of querySelector : CSS Selectors: querySelector uses CSS selectors to find elements on the page. This means you can select elements based on their IDs, classes, types, or any other CSS attribute. Element Return: The querySelector method returns the first element that matches the specified selector. If no element is found, it returns null. Functionality: The querySelector method traverses the DOM from the element where it is called (usually document to select from the entire document) and returns the first element that matches the provided selector, following the depth-first search and order of encounter. Here's an example of using querySelector in TypeScript: Suppose you have a button in...

toLowerCase() is a method in TypeScript (and in JavaScript ) that converts all characters in a string to lowercase. It doesn't modify the original string, but instead returns a new string with all letters converted to lowercase. Here's an example of how to use toLowerCase() in TypeScript: In this example, myString contains the original string "Hello World!" , and lowerCaseString contains the resulting string after calling toLowerCase() , which is "hello world!" . Here's a more practical use case: Suppose you have a form where users can input their emails. To ensure there are no capitalization issues when comparing emails later (e.g., when checking if an email is already registered) , you can convert all emails to lowercase before saving them to the database. This ensures that even if the user enters their email with uppercase letters or a mixture of cases, it will still be recognized as the same email. This way, when you need to compare emails, you...