点击事件监听器

Question

I'm working on an Electron-based application, and I don't have much experience with it or JavaScript or Node.js. Currently, I just want to close a window by a click on a button.

close.addEventListener('click', function () {
    ipc.send('close-main-window')
})

This totally works! I am just confused with why it works. From what I understand, the first argument in addEventListener is just any arbitrary string. However, I don't specifically write anything to handle a 'click'. This should mean it's built in functionality, I think. Is this part of JavaScript, Node.js, or Electron? And where in the documentation can I find a list of built in events?

Answer 1

JavaScript has the function addEventListener which adds an event listener (surprise, surprise) to an element. The element in which the listener is applied to now listens for an event, a string passed into the function (in this case click). Once the event is triggered (in this case when a user clicks on the element), it will execute the callback, which is the function you declared. So, consider this:

element.addEventListener("click", function() {
    console.log("hello!");
});

This will log hello every time element is clicked.

You can read more at the Mozilla's Documentation . Here's a list of all the available events.

Answer 2

The first argument is string which represent the event type .

I think internally it works like this

var event = new Event('click');

where Event is an event object & click is already a predefined event of javascript