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Javascript 选择元素onchange_Javascript_Select_Element - Fatal编程技术网

Javascript 选择元素onchange

Javascript 选择元素onchange,javascript,select,element,Javascript,Select,Element,如果选择了select元素,我如何访问它 var select = document.getElementById("select"); if(select.selected == true) doesnt work any idea? document.getElementById(“mySelect”).value 或 var selObj=document.getElementById(“mySelect”); selObj.options[selObj.selectedIndex].

如果选择了select元素,我如何访问它

var select = document.getElementById("select");
if(select.selected == true)

doesnt work any idea?
document.getElementById(“mySelect”).value

var selObj=document.getElementById(“mySelect”);
selObj.options[selObj.selectedIndex].value

DOM树类似于

Select
|-option
|-option
`-option

它不是可以选择的选择节点。因此,您需要获取选择,浏览子项,并测试是否选择了子项,直到找到为止。

我们是否可以知道您尝试选择的元素的类型,例如复选框、单选按钮等。我通常会在列表的开头有一个项,如[select Value]。然后测试selectedIndex>0