热来获取所选文本和selectedIndex在选择？

Question

我需要在提交下拉列表中获取所选文本和selectedIndex。以下代码返回第一个索引始终为0，第一个选项为text..for例如，如果我选择了三个，则显示0索引和一个文本..

function myfunc()
 {
    `enter code here`var x = document.getElementById("listt").selectedIndex;
    var y = document.getElementById("listt").options;
    alert("Index: " + y[x].index + " is " + y[x].text);
}
 <select id="listt" >
   <option >one</option>
    <option >two</option>
     <option>three</option>
     <option >four</option>
    </select>

<input type="Submit" value="submit " name="Submit" onclick="myfunc()"></input>

Answer 1

试试这段代码。

<select id="listt" >
    <option >one</option>
    <option >two</option>
    <option>three</option>
    <option >four</option>
</select>

<input id="btnSubmit" type="Submit" value="submit " name="Submit" />


function myfunc() {
    var x = document.getElementById("listt").selectedIndex;
    var y = document.getElementById("listt").options;
    alert("Index: " + y[x].index + " is " + y[x].text);
}
document.getElementById ("btnSubmit").addEventListener ("click", myfunc, false);