js实现select下拉框菜单

本文实例讲述了js实现select下拉框菜单的详细代码。分享给大家供大家参考。具体如下：
运行效果截图如下：

具体代码如下：

<!DOCTYPE html>

<html>

<head>
 <title></title>
 <style type="text/css">
  #gridComboBox {
  background: #fff;
  border: 1px solid #2d78f4;
  border-radius: 2px;
  -moz-box-shadow: inset 0 0 4px #06c;
  -webkit-box-shadow: inset 0 0 4px #06c;
  box-shadow: inset 0 0 4px #06c;
 }
 </style>
</head>

<body>
 <input onclick="doClick(this,'ddd(aa/bb/cc/erererer/dfdfdfdfdfdfdfdfdfdfdfdfdf/ejjejrjerjer//erererer ////////)eee')" />
 <input onclick="doClick(this,'ddd(aa/bb/cc/erererer/dfdfdfdfdfdfdfdfdfdfdfdfdf/ejjejrjerjer//erererer ////////)eee')" style='width: 300px;' />
 <p><b>Needed Properties:</b> sender.offsetTop & sender.offsetLeft & sender.offsetHeight</p>
</body>

</html>
<script type="text/javascript">

function delGridComboBox() { // 删除弹出框
 var divContainer = document.getElementById('gridComboBox');
 if (divContainer) {
  divContainer.parentNode.removeChild(divContainer);
 }
}

function doClick(sender, str) {//str='ddd(aa/bb/cc/erererer/dfdfdfdfdfdfdfdfdfdfdfdfdf/ejjejrjerjer//erererer ////////)eee' 只取()得内容/分割做为数据源

 delGridComboBox();

 // console.log(sender);
 // for(var i in sender)
 // {
 //  console.log(i+"|"+sender[i]);
 // }

 var re = /[^\)\(]*/g //取出()中的内容作为下拉数据源
 var fit = str.match(re);
 var fmt = fit[2].split('/');

 var divContainer = document.createElement('div');
 divContainer.style.width = sender.clientWidth + 2 + "px";
 divContainer.style.overflow = "hidden";
 divContainer.style.position = 'absolute';
 divContainer.style.top = sender.offsetTop + sender.offsetHeight + 'px';
 divContainer.style.left = sender.offsetLeft + 'px';
 divContainer.style.zIndex = 999;
 divContainer.id = "gridComboBox";

 for (var i = 0; i < fmt.length; i++) {  

  console.log('fmt[i]>>', fmt[i]);
  var txt = document.createElement('div');
  txt.innerHTML = fmt[i];
  txt.title = txt.innerHTML;
  txt.style.margin = 3+'px';
  txt.addEventListener('mouseover', function changeBg(event) {
   event.target.style.fontWeight = 'bold';
   event.target.style.color = 'white';
   event.target.style.backgroundColor = '#2d78f4';
  }, false);
  txt.addEventListener('mouseout', function unChangeBg(event) {
   event.target.style.fontWeight = 'normal';
   event.target.style.color = 'black';
   event.target.style.backgroundColor = 'white';
  }, false);
  txt.onclick = function(subSender) {
   sender.value = subSender.target.innerText;
   delGridComboBox();
  };
  divContainer.appendChild(txt);
 };

 document.body.appendChild(divContainer);
};
</script>

如果大家还想深入学习，可以点击jquery下拉框效果汇总、JavaScript下拉框效果汇总进行学习。

以上就是js实现select下拉框菜单的代码，希望本文所述对大家学习javascript程序设计有所帮助。