Salesforce JavaScript Developer Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The lifecycle hook that is executed when a Lightning Web Component is inserted into the DOM is the connectedCallback() method. This method is a part of the lifecycle of a Lightning Web Component and is called when the component is inserted into the DOM, making it an ideal place to perform tasks such as fetching data, setting up event listeners, or initiating any necessary setup for the component.

When the connectedCallback() is triggered, the component has been added to the DOM, and you can safely interact with other parts of the component hierarchy and make adjustments based on its environment. This is crucial for ensuring that the component is fully functional before it is rendered to the user.

In contrast, the constructor() method is primarily for initializing properties and should not contain any code that interacts with the DOM, as it is called before the component is connected. The renderedCallback() is executed after the component's template has been rendered, making it suitable for DOM-related operations that need to happen post rendering. Finally, the disconnectedCallback() is called when the component is removed from the DOM, so it is used for cleanup operations rather than for executing tasks upon insertion.