如何在firefox中使用javascript來觸發鼠標事件？

Question

我想用javascript觸發組合框/選擇框的鼠標按下事件。這裏是代碼，它在crome中完美工作，但不在Firefox中。對此有何幫助？

<select id="dropdown"> 
    <option value="Red">Red</option> 
    <option value="Green">Green</option> 
    <option value="Blue">Blue</option> 
</select> 
<br> 
<button id="fire" type="button" onclick="runThis()">Show dropdown items</button> 

// <select> element displays its options on mousedown, not click. 
showDropdown = function (element) { 
    var event; 
    event = document.createEvent('MouseEvents'); 
    //event.initMouseEvent('mousedown', true, true, window); 
    event.initMouseEvent('mousedown', true, true, window,0, 0, 0, 0, 0, false, false, false, false, 0, null); 
    element.dispatchEvent(event); 
}; 

// This isn't magic. 
window.runThis = function() { 
    var dropdown = document.getElementById('dropdown'); 
    showDropdown(dropdown); 
}; 

在此先感謝....

Answer 1

這似乎只是這是不可能的。看到類似的問題：

• How can you programmatically tell an HTML SELECT to drop down (for example, due to mouseover)?
• Show select dropdown in jQuery?
• Click trigger on select box doesn't work in jQuery