直接上代码。如果乱码的话，看下文件的编码格式，可以改成utf-8。
<HTML> <HEAD> <META http-equiv='Content-Type' content='text/html; charset=gb2312'> <TITLE></TITLE> </HEAD> <BODY> <div style="position:relative;"> <span style="margin-left:100px;width:18px;overflow:hidden;"> <select style="width:118px;margin-left:-100px" onchange="this.parentNode.nextSibling.value=this.value"> <option value="测试1">测试1</option> <option value="测试2">测试2</option> <option value="测试3">测试3</option> </select></span><input name="box" style="width:100px;position:absolute;left:0px;"> </div> </BODY> </HTML>