代码如下：
<html>
<head>
<title>Test</title>
function onDdlSelecting(ddl) {
if (!ddl.bypass) {
ddl.bypass = true;
document.getElementById("label").innerText = ddl.id + " is selecting
";
} else {
ddl.bypass = false;
}
}
function onDdlIdle() {
if (event.propertyName == 'value') {
document.getElementById("label").innerText = "Idle";
}
}
</script> </head>
<body>
<div>
<span>ddl1</span>
<select id="ddl1" onclick="onDdlSelecting(this);" onpropertychange="onDdlIdle();">
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<span>ddl2</span>
<select id="ddl2" onclick="onDdlSelecting(this);" onpropertychange="onDdlIdle();">
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<br />
<br />
<br />
<br />
<br />
<div style="border: solid 1px black; background-color: silver; padding: 5px 5px 5px 5px;">
<span>Status: </span><span id="label">Idle</span></div>
</div>
</body>
</html>
<head>
<title>Test</title>
<script type="text/javascript">
function onDdlSelecting(ddl) {
if (!ddl.bypass) {
ddl.bypass = true;
document.getElementById("label").innerText = ddl.id + " is selecting
";} else {
ddl.bypass = false;
}
}
function onDdlIdle() {
if (event.propertyName == 'value') {
document.getElementById("label").innerText = "Idle";
}
}
</script> </head>
<body>
<div>
<span>ddl1</span>
<select id="ddl1" onclick="onDdlSelecting(this);" onpropertychange="onDdlIdle();">
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<span>ddl2</span>
<select id="ddl2" onclick="onDdlSelecting(this);" onpropertychange="onDdlIdle();">
<option value="1">One</option>
<option value="2">Two</option>
<option value="3">Three</option>
</select>
<br />
<br />
<br />
<br />
<br />
<div style="border: solid 1px black; background-color: silver; padding: 5px 5px 5px 5px;">
<span>Status: </span><span id="label">Idle</span></div>
</div>
</body>
</html>