我已经实现了导航栏，以及如何首先使用javascript显示所选选项
function getoptions(){
var x =document.getElementById("languagelist");
var y = document.getElementById("language");
y.innerHTML= // set the selected language
}<nav>
<div class="dropdown">
<button id="language" class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown"
aria-haspopup="true" aria-expanded="false">
English
</button>
<div id="languagelist" class="dropdown-menu" aria-labelledby="dropdownMenu2" onclick="getoptions()">
<a class="dropdown-item" href="/en">English</a>
<a class="dropdown-item" href="/fr">French</a>
</div>
</div>
</nav>最佳答案
这种纯JavaScript解决方案将为您工作。运行并测试
<html>
<head>
<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">
<!-- jQuery library -->
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.0/jquery.min.js"></script>
<!-- Latest compiled JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/js/bootstrap.min.js"></script>
</head>
<body>
<nav>
<div class="dropdown">
<button id="language" class="btn btn-warning dropdown-toggle" type="button" id="dropdownMenu2"
data-toggle="dropdown" aria-haspopup="true" aria-expanded="false" onclick="clickButton()">
English
</button>
<div id="languagelist" class="dropdown-menu" aria-labelledby="dropdownMenu2" onclick="clickItem(); return false">
<a class="dropdown-item" href="/en">English</a>
<a class="dropdown-item" href="/fr">French</a>
</div>
</div>
</nav>
</body>
<script>
function clickButton() {
document.getElementById("languagelist").click();
}
function clickItem() {
var element = document.getElementById("languagelist");
for (var i = 0; i < element.children.length; i++) {
(function(index) {
element.children[i].onclick = function() {
var thetext = element.getElementsByTagName('a')[index].innerHTML;
// var thehref = element.getElementsByTagName('a')[index].href; get the href here once you hosted, for testing I will use the name
var buttonelement = document.getElementById("language");
buttonelement.innerText = thetext;
window.open("/"+thetext);
}
})(i);
}
}
</script>
</html>希望这对某人有帮助。干杯！