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显示dropdownlist项取决于使用javascript的另一个dropdownlist项_Javascript_Html - Fatal编程技术网

显示dropdownlist项取决于使用javascript的另一个dropdownlist项

显示dropdownlist项取决于使用javascript的另一个dropdownlist项,javascript,html,Javascript,Html,我想显示一个dropdownlistname子类别项,该子类别项依赖于另一个dropdownlistproblem类型项 问题类型:从问题类型中选择一种:行问题、服务问题、, 设备问题和账单问题 子类别: 线路问题–线路噪音、呼叫干扰、线路损坏 服务问题–供应商的重大服务中断 设备问题-噪音大、无拨号音、设备损坏 账单问题–账单支付未更新,账单错误 这是我的密码 <html> <head> <meta http-equiv="Content-Type" co

我想显示一个dropdownlistname子类别项,该子类别项依赖于另一个dropdownlistproblem类型项

问题类型:从问题类型中选择一种:行问题、服务问题、, 设备问题和账单问题

子类别:

线路问题–线路噪音、呼叫干扰、线路损坏

服务问题–供应商的重大服务中断

设备问题-噪音大、无拨号音、设备损坏

账单问题–账单支付未更新,账单错误

这是我的密码

<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
    <title>Insert title here</title>
    <script type="text/javascript">
        window.onload = function addList(){
            int i;
            var sub = document.forms["raiseNewFault2"]["sub_category"];
            var main = document.forms["raiseNewFault2"]["problem_type"].value;
            var str1 = new Array("Noisy Line", "Call Interference", "Line damage");
            var str2 = new Array("Major service outage at Provider");
            var str3 = new Array("Noisy", "No Dial Tone", "Damaged Equipment");
            var str4 = new Array("Billing paid not updated", "Wrong Billing");
            if(main.equals("Line issue")){
                for(i=0;i<=2;i++){
                    var option = document.createElement('option');
                    option.text = option.value = str1[i];
                }
            }
            else if(main.equals("Service issue")){
                for(i=0;i<=0;i++){
                    var option = document.createElement('option');
                    option.text = option.value = str2[i];
                }
            }
            else if(main.equals("Equipment issue")){
                for(i=0;i<=2;i++){
                    var option = document.createElement('option');
                    option.text = option.value = str3[i];
                }
            }
            else if(main.equals("Billing issue")){
                for(i=0;i<=1;i++){
                    var option = document.createElement('option');
                    option.text = option.value = str4[i];
                }
            }
            select.add(option);
        }
    </script>
    <style type="text/css">
        #raiseNewFault2Div
        {
            margin-top : 25px;
            margin-left : 325px;
            height : 500px;
            width : 600px;
            background-color : #FFDA91;
            border : ridge;
            border-width : "3px"
        }
    </style>
</head>
<body onload="addList()">
    <div id="raiseNewFault2Div">
        <center>
            <form name="raiseNewFault2" action="Controller" method="post">

                <br/><br/>
                <font size="3" color="#006E25">Problem type &nbsp;&nbsp; :   
                 &nbsp;&nbsp; </font>
                <select name="problem_type">
                    <option value="Line issue" selected>Line issue</option>
                    <option value="Service issue">Service issue</option>
                    <option value="Equipment issue">Equipment issue</option>
                    <option value="Billing issue">Billing issue</option>
                </select>
               <br/><br/><font size="3" color="#006E25">Sub Category &nbsp;&nbsp; :   
                &nbsp;&nbsp; </font>
                <select name="sub_category"></select>
                </from></center> </div></body></html>

最简单的方法是检查用户在第一个列表中选择了什么,然后使用javascript替换整个第二个列表:-
document.getElementByIdput此处包含列表的div的id。innerHTML=将要替换为旧列表的列表放在此处

我可以简单地用代码来回答,但这个网站并不适合它

您可能需要检查以下内容:

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