Javascript下拉列表没有响应

Javascript dropdownlist doesn't respond

本文关键字:响应 下拉列表 Javascript      更新时间:2023-09-26

表单一开始就隐藏了。当我选择窗口,窗体应该是可见的,但它没有。我试图添加一个if-else语句,如果没有匹配,它将显示警报,但这也不起作用。我猜它永远不会着火。有人知道为什么吗?

代码如下:

<asp:Content ID="Content2" ContentPlaceHolderID="HeaderContent" Runat="Server">
<script src="http://ajax.aspnetcdn.com/ajax/jQuery/jquery-1.8.2.min.js" type="text/javascript"></script>
<script type="text/javascript">
    function DropDownlistOptions() {
        var dropdownlist = document.getElementById("DropDownListForm");
        var selected = dropdownlist.options[dropdownlist.selectedIndex].value;
        if (selected == "Window") {
            document.getElementById("WindowForm").style.visibility = "visible";
        }
        else {
            alert("failed");
        }
    }
</script>
</asp:Content>
<asp:Content ID="Content3" ContentPlaceHolderID="Content1" Runat="Server">
<asp:DropDownList ID="DropDownListForm" runat="server" onchange="DropDownlistOptions()">
        <asp:ListItem Selected="True">Please Select</asp:ListItem>
        <asp:ListItem>Window</asp:ListItem>
        <asp:ListItem>Linux</asp:ListItem>
</asp:DropDownList>
<div id="WindowForm" style="visibility:hidden;">
    Form info to fill.....
</div>
</asp:Content>

我找到了一个解决方案,我只需要添加

document.getElementById("<%=DropDownListForm.ClientID%>");