Html 如何在选择标签的更改时调用 JavaScript 函数？
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How to call a JavaScript function onchange of a select tag?
提问by laxmi
Below is my JavaScript:
下面是我的 JavaScript：
<script language="JavaScript">
function checkit()
{
var state=document.frm.getElementById(stateS)
if (state="Please select a state")
{
document.frm.Month.disable = true;
}
else
{
document.frm.Month.enable = true;
}
}</script>
and I call checkit()function in it from below <select>tag:
我checkit()从下面的<select>标签调用函数：
<td align="left"><g:select name="Month" from="${month.values()}" optionValue="${Month}" onChange=checkit()/></td>
</tr>
I have a select tag for state and until I select any state the month select box should be disabled. Can anyone tell me where I went wrong?
我有一个状态选择标签，在我选择任何状态之前，应该禁用月份选择框。谁能告诉我我哪里出错了？
回答by Hussam Sibai
actually there is a " missing there, it should be
实际上有一个“失踪”，应该是
onChange="checkit();"
回答by Jonas Elfstr?m
Change the onchangeto onChange="checkit(this);and then something like the below in checkit
更改onchange为onChange="checkit(this);，然后类似于下面的checkit
function checkit(selectObj)
{
var idx = selectObj.selectedIndex;
document.frm.Month.disabled = idx == 0;
}
回答by Alonso Mulgado
by id jquery-1.9.1
通过 id jquery-1.9.1
$('#selectBox').on('change', function()
{
value= this.value;
if(value==0)
{
//code
}
else if(value==1)
{
//code
}
...
else
{
//code
}
});
回答by Okaba Mac
document.querySelector("select").onchange = function() {myFunction()};
document.querySelector("select").onchange = function() {myFunction()};
回答by letsjump
I needed to put its javascript function beforethe input tag is generated.
EG.outside jourJSframework(document).ready function or before the <\head> closing tag of your html document.
我需要在生成输入标签之前放置它的 javascript 函数。
EG.outside jourJSframework(document).ready 函数或在您的 html 文档的 <\head> 结束标记之前。
