Question

我正在设计一个这样的网页：

<html>
<head>
<title>Bug UI</title>
</head>

<body>

<script>
    function myfunc()
    {
    //what goes here??
    }
</script>
<form>
    <select name = "parameters">
        <option value = "param1">Param 1</option>
        <option value = "param2">Param 2</option>
        <option value = "param3">Param 3</option>
        <option value = "param4">Param 4</option>
        <option value = "param5">Param 5</option>
    </select>
    <input type = "button" onclick = "myfunc()" value = "Submit">
</form>
</body>
</html>

它显示一个下拉框，当我从框中选择一个值（比如Param 1）并单击“提交”时，我需要打印该值（在这种情况下为Param 1）。怎么做到这一点？

Answer 1

var s = document.getElementsByName('parameters')[0];
var text = s.options[s.selectedIndex].text;

Answer 2

完美地尝试这项工作：

var ex = document.getElementsByTagName('select');
var str= ex.options[ex.selectedIndex].value;
 **or**
var str= ex.options[ex.selectedIndex].text;

或

var ex = document.getElementsByName('parameters')[0]; var str= ex.options[ex.selectedIndex].value; **or** var str= ex.options[ex.selectedIndex].text;

Answer 3

试试这个：

function myfunc() {
   var par=document.getElementsByName('parameters')[0];
   var index=par.selectedIndex
   console.log(par.options[index].text);
}

如何使用JS打印HTML下拉框中选择的值

3 个答案: