javascript 直到第二个实例才会触发下拉 onchange 事件
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dropdown onchange event not firing until second instance
提问by jkeefe56
I am having the strangest problem, although I'm sure it's something simple - I'm stumped. I have an event that hides and shows divs based on a dropdown menu. When I pick something from my menu it does absolutely nothing. However, if I change it to a second selection, it works perfectly. Anyone know what I screwed up? Thanks for any and all assistance.
我遇到了最奇怪的问题，虽然我确定这很简单 - 我很难过。我有一个基于下拉菜单隐藏和显示 div 的事件。当我从菜单中选择一些东西时，它绝对没有任何作用。但是，如果我将其更改为第二个选择，则效果很好。有谁知道我搞砸了什么？感谢您的任何帮助。
function call1()
{
document.getElementById("quest1").onchange = function () {
alert("ON CHANGE FIRED");
var val = this.options[this.selectedIndex].value;
document.getElementById("area1z").style.display = (val == "0") ? "block" : "none";
document.getElementById("area1a").style.display = (val == "1") ? "block" : "none";
document.getElementById("area1b").style.display = (val == "2") ? "block" : "none";
document.getElementById("area1c").style.display = (val == "3") ? "block" : "none";
document.getElementById("area1d").style.display = (val == "4") ? "block" : "none";
};
}
<select id="quest1" onChange="call1()">
<option value=0></option>
<option value=1>Stretch (Maintaining a lifestyle choice for an amount of time) </option>
<option value=2>Sum (i.e. saving money, counting workouts, etc.</option>
<option value=3>Loss (i.e. Weightloss)</option>
<option value=4>None</option>
</select>
<div id=area1z style="display:none">Please Choose a Quest</div>
<div id=area1a style="display:none">Stretch</div>
<div id=area1b style="display:none">Sum</div>
<div id=area1c style="display:none">Loss</div>
<div id=area1d style="display:none">None</div>
回答by Dhaval Marthak
Remove onChange()from following:
onChange()从以下内容中删除：
<select id="quest1" onChange="call1()">
Write in this way:
这样写：
document.getElementById("quest1").onchange = function () {
alert("ON CHANGE FIRED");
var val = this.options[this.selectedIndex].value;
document.getElementById("area1z").style.display = (val == "0") ? "block" : "none";
document.getElementById("area1a").style.display = (val == "1") ? "block" : "none";
document.getElementById("area1b").style.display = (val == "2") ? "block" : "none";
document.getElementById("area1c").style.display = (val == "3") ? "block" : "none";
document.getElementById("area1d").style.display = (val == "4") ? "block" : "none";
};
回答by shemy
<script>
function call1()
{
alert("ON CHANGE FIRED");
var val=document.getElementById("quest1").value;
alert(val);
document.getElementById("area1z").style.display = (val == "0") ? "block" : "none";
document.getElementById("area1a").style.display = (val == "1") ? "block" : "none";
document.getElementById("area1b").style.display = (val == "2") ? "block" : "none";
document.getElementById("area1c").style.display = (val == "3") ? "block" : "none";
document.getElementById("area1d").style.display = (val == "4") ? "block" : "none";
}
</script>
<select id="quest1" onChange="call1()">
<option value="0"></option>
<option value="1">Stretch (Maintaining a lifestyle choice for an amount of time) </option>
<option value="2">Sum (i.e. saving money, counting workouts, etc.</option>
<option value="3">Loss (i.e. Weightloss)</option>
<option value="4">None</option>
</select>
<div id="area1z" style="display:none">Please Choose a Quest</div>
<div id="area1a" style="display:none">Stretch</div>
<div id="area1b" style="display:none">Sum</div>
<div id="area1c" style="display:none">Loss</div>
<div id="area1d" style="display:none">None</div>
回答by varun
Here is a Demo that you are trying to do.
这是您正在尝试执行的演示。
Either you remove the "onchaange" or the "document.getElementById("quest1").onchange = function () {}" from the code.
您可以从代码中删除“onchaange”或“document.getElementById("quest1").onchange = function () {}”。
document.getElementById("quest1").onchange = function () {
alert("ON CHANGE FIRED");
var val = this.options[this.selectedIndex].value;
document.getElementById("area1z").style.display = (val == "0") ? "block" : "none";
document.getElementById("area1a").style.display = (val == "1") ? "block" : "none";
document.getElementById("area1b").style.display = (val == "2") ? "block" : "none";
document.getElementById("area1c").style.display = (val == "3") ? "block" : "none";
document.getElementById("area1d").style.display = (val == "4") ? "block" : "none";
};
jsfiddle link: http://jsfiddle.net/2M74g/1/
jsfiddle 链接：http: //jsfiddle.net/2M74g/1/
