如何獲得焦點事件觸發器？

Question

僅使用 javascript，我想知道焦點事件是由單擊“選擇”標簽觸發的，還是由選項卡觸發的。 可能嗎？

Answer 1

你可以像這樣檢查它：

 const select = document.getElementById("number"); select.addEventListener("keyup", myFunction); function myFunction(e) { if(e.key === 'Tab'){ console.log('I am a focus event was triggered by using tab') } } select.addEventListener("mousedown", myFunction2); function myFunction2(){ console.log('I am a focus event was triggered by a click') }

 <label for="cars">Choose a number:</label> <select name="cars" id="number" > <option value="volvo">1</option> <option value="saab">2</option> <option value="opel">3</option> <option value="audi">4</option> </select>