16 lines
579 B
Markdown
16 lines
579 B
Markdown
The answer: `1` and `2`.
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The first handler triggers, because it's not removed by `removeEventListener`. To remove the handler we need to pass exactly the function that was assigned. And in the code a new function is passed, that looks the same, but is still another function.
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To remove a function object, we need to store a reference to it, like this:
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```js
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function handler() {
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alert(1);
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}
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button.addEventListener("click", handler);
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button.removeEventListener("click", handler);
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```
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The handler `button.onclick` works independantly and in addition to `addEventListener`.
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