我正在尝试通过 javascript 操作下拉列表,但似乎每次单击按钮时都会得到此代码:
类型错误:objDropDownMenu.options 未定义
objDropDownMenu.options[1].selected = true;
这是我的代码:
<FORM NAME="myform" ACTION="" METHOD="GET">
<SELECT class="select diff_data" style="WIDTH: 165px" name=CarPick>
<OPTION value=1>Audi</OPTION>
<OPTION value=2>BMW</OPTION>
<OPTION value=3>Mercedes</OPTION>
</SELECT>
<INPUT TYPE="button" NAME="button2" Value="Write" onClick="writeText(this.form)">
</FORM>
<SCRIPT LANGUAGE="JavaScript">
var objDropDownMenu = document.getElementsByName("CarPick");
function writeText (form) {
objDropDownMenu.options[30].selected = true;
}
</SCRIPT>
安宇知道为什么?谢谢!