表单 - 下拉列表中的先前所选值到电子邮件

我创建了一个新表单。尽管onchange"systemUpdate"看起来工作正常，但在提交表单后，它会发布到电子邮件，并且电子邮件显示以前选择的选项值，这些值在提交表单之前已更改和更新。

（#Wyse_Terminaldiv），然后改变主意并选择 selectedIndex == 2 并提交，"PS/2 连接"仍显示在电子邮件中。

如何清除以前选择的选项值，以便它们不会最终出现在电子邮件中？有合理数量的代码，所以只包含相关的脚本和html

function systemUpdate(detail) {
if (detail.selectedIndex == 0) {
    $("#Option_Terminal").hide();
    $("#Wyse_Terminal select").removeAttr("class");
    $("#Wyse_LaptopDesktop").hide();
    $("#Wyse_LaptopDesktop select").removeAttr("class");
    $("#HP_Terminal").hide();
    $("#HP_Terminal select").removeAttr("class");
} else if (detail.selectedIndex == 1) {
    $("#Wyse_Terminal").show();
    $("#Wyse_Terminal select").addClass("required");
    $("#Wyse_LaptopDesktop").show();
    $("#Wyse_LaptopDesktop select").addClass("required");
    $("#HP_Terminal").hide();
    $("#HP_Terminal select").removeAttr("class");
} else if (detail.selectedIndex == 2) {
    $("#Wyse_Terminal").hide();
    $("#Wyse_Terminal select").removeAttr("class");
    $("#Wyse_LaptopDesktop").show();
    $("#Wyse_LaptopDesktop select").addClass("required");
    $("#HP_Terminal").hide();
    $("#HP_Terminal input").removeAttr("class");
} else if (detail.selectedIndex == 3) {
    $("#Wyse_Terminal").hide();
    $("#Wyse_Terminal select").removeAttr("class");
    $("#Wyse_LaptopDesktop").hide();
    $("#Wyse_LaptopDesktop select").removeAttr("class");
    $("#HP_Terminal").show();
    $("#HP_Terminal select").addClass("required");
}}
<form method="POST" title="myForm" id="myForm" name="myForm" action="emailTemplate.php">
    <fieldset>
    <legend>Select Your System</legend>
    <p><label>Please select your system</label>
        <select id="select_system" name="select_system" class="required" onchange="systemUpdate(this);">
            <option value="">Select...</option>
            <option value="Wyse Terminal">Wyse Terminal</option>
            <option value="Laptop/Desktop">Laptop/Desktop</option>
            <option value="HP Terminal">HP Terminal</option>
        </select> *
    <p><img style="width: 611px;"src="images/systemtype.jpg"/></p>
    </p>
<br />
<div id="Wyse_Terminal">
    <p><label>Please select connection type</legend>
        <select id="Connection_Type" name="Connection_Type" class="required">
            <option value="">Select...</option>
            <option value="PS/2 connections">PS/2 connections</option>
            <option value="USB connections">USB connections</option>
        </select> *
    <p><img style="width: 611px;"src="images/mouse.png"/></p>
    </p>
</div>
<br />
<div id="Wyse_LaptopDesktop">
    <p><label>Select items required</label>
        <select id="Items_Required" name="Items_Required" class="required">
            <option value="">Select...</option>
            <option value="Keyboard and Mouse ($60)">Keyboard and Mouse ($60)</option>
            <option value="Keyboard only ($40)">Keyboard only ($40)</option>
            <option value="Mouse only ($20)">Mouse only ($20)</option>
        </select> * 
    </p>
</div>
<div id="HP_Terminal">
    <p><label>If HP Terminal</label>
        <select id="HPTerminal" name="HPTerminal" class="required">
            <option value="">Select...</option>
            <option value="Wireless Keyboard and Mouse ($60)">Wireless Keyboard and Mouse ($60)</option>
        </select> *
    </p>
</div>
</fieldset>

<fieldset id="yourDetails">
</fieldset>
<p class="submit"><input class="button" onClick="return checkTicked();" name="Submit" type="submit" value="Submit"></p>

感谢您帮助新手！