When someone interacts with a webpage, the browser sends events to the relevant JavaScript code. The selectstart event happens when the user starts selecting text.
When selectstart happens
The user starts selecting text.
You can listen for it using addEventListener(). That keeps event handling separate from HTML attributes such as onclick and works well with modern code organization.
A small working example
<p id="demo-target">Select this sentence or inspect the page.</p>
<p id="event-status" role="status">Waiting for selectstart...</p>
<script>
const eventTarget = document;
const eventStatus = document.getElementById("event-status");
if (eventTarget) {
eventTarget.addEventListener("selectstart", (eventDetails) => {
eventStatus.textContent = "selectstart event received";
console.log(eventDetails.type, eventDetails.target);
});
}
</script>Reading the code
The browser listens for selectstart on the relevant target. When the event occurs, the callback receives eventDetails, updates the status message and logs the event name and target in Developer Tools.
Begin dragging across text; it may be cancelable.
Some events need a specific browser condition, another tab or window, or a Web Component to reproduce. Read the trigger steps carefully before deciding that an event handler is not working.
Try it in your browser
Open the page, show the Console panel, and follow this test: Begin dragging across text; it may be cancelable. Then change one thing in the example and observe whether the event still fires.
Common Beginner Mistakes
- Expecting
selectstartto fire without its required user action or browser condition. - Begin dragging across text; it may be cancelable.
- Adding repeated event listeners without considering cleanup or unwanted side effects.
Key Takeaways
selectstartreports the user starts selecting text.addEventListener("selectstart", ...)listens for the event on the appropriate target.- Begin dragging across text; it may be cancelable.