怎样动态创建和删除一个HTML控件,例如下拉框?

Question

<form name=formess>
<select name=selects12>
<option></option>
</select>
  <input name=dd type=button value="增加一项" onclick=addones()>
</form>
<script>
 function addones()
  {
    len1=document.formess.selects12.options.length
    document.formess.selects12.options[len1]=new Option(len1,"value","","selected")
  }
</script>

Answer 1

以text框为例：var oInput = document.createElement("input");
oInput.type = "text";
oInput.name = "userName"
oInput.value = "lxc":
document.body.appendChild(oInput);删除：document.body.removeChild(document.all.userName);