IE浏览器移除select下拉选按钮图标

IE浏览器移除下拉选按钮的方法！

1. https://codepen.io/vkjgr/pen/VYMeXp；
2. https://codepen.io/jackocnr/pen/lmAeh；
3. http://m.blog.csdn.net/article/details?id=42268329；
4. http://stackoverflow.com/questions/19407332/how-to-hide-drop-down-arrow-in-ie8-ie9；
5. https://harvesthq.github.io/chosen/；
6. http://stackoverflow.com/questions/20163079/remove-select-arrow-on-ie；