How to determine what is selected in the drop开发者_JAVA百科 down? In Javascript.
If your dropdown is something like this:
<select id="thedropdown">
<option value="1">one</option>
<option value="2">two</option>
</select>
Then you would use something like:
var a = document.getElementById("thedropdown");
alert(a.options[a.selectedIndex].value);
But a library like jQuery simplifies things:
alert($('#thedropdown').val());
Use the value
property of the <select>
element. For example:
var value = document.getElementById('your_select_id').value;
alert(value);
<select onchange = "selectChanged(this.value)">
<item value = "1">one</item>
<item value = "2">two</item>
</select>
and then the javascript...
function selectChanged(newvalue) {
alert("you chose: " + newvalue);
}
var dd = document.getElementById("dropdownID");
var selectedItem = dd.options[dd.selectedIndex].value;
Like this:
$dd = document.getElementById("yourselectelementid");
$so = $dd.options[$dd.selectedIndex];
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