如何从DOM访问选择框选项的"显示"文本？

Question

给出以下HTML:

<select name="my_dropdown" id="my_dropdown">
<option value="1">displayed text 1</option>
</select>

如何使用Javascript/DOM获取字符串"显示的文本1"？

Answer 1

var sel = document.getElementById("my_dropdown");

//get the selected option
var selectedText = sel.options[sel.selectedIndex].text;

//or get the first option
var optionText = sel.options[0].text;

//or get the option with value="1"
for(var i=0; i<sel.options.length; i++){
    if(sel.options[i].value == "1"){
        var valueIsOneText = sel.options[i].text;
    }
}