asp.net-mvc - 2つのフォームを持つMVCビュー、なぜ両方が同じアクションにレンダリングされるのですか？

Question

@using (Html.BeginForm("Unassign", "Terminals_DataGroups"))
{ 
    @Html.HiddenFor(m => m.DeviceId)
    @Html.HiddenFor(m => m.DataGroupId)
    <input type="submit" value="Remove group from device" @(string.IsNullOrEmpty(Model.DataGroupName) ? "disabled=\"disabled\"" : "") />
}

@using (Html.BeginForm("Assign", "Terminals_DataGroups"))
{ 
    @Html.HiddenFor(m => m.DeviceId)

    <div class="editor-label">
        @Html.LabelFor(model => model.DataGroups)
    </div>
    <div class="editor-field">
        @Html.DropDownListFor(model => model.DataGroupsSelectedItem, new SelectList(Model.DataGroups, "Value", "Text"))
        @Html.ValidationMessageFor(model => model.DataGroupsSelectedItem)
    </div>

    <input type="submit" value="Assign Data Group" />
}

しかし、HTMLは次のようにレンダリングされます。

<form action="/Terminals_DataGroups/Assign" method="post">
    <input data-val="true"
        data-val-number="The field DeviceId must be a number."
        data-val-required="The DeviceId field is required."
        id="DeviceId"
        name="DeviceId"
        type="hidden"
        value="15" />
    <input data-val="true"
        data-val-number="The field DataGroupId must be a number."
        id="DataGroupId"
        name="DataGroupId"
        type="hidden"
        value="1" />
    <input type="submit" value="Remove group from device"  />
</form>

<form action="/Terminals_DataGroups/Assign" method="post">
    <input data-val="true"
        data-val-number="The field DeviceId must be a number."
        data-val-required="The DeviceId field is required."
        id="DeviceId"
        name="DeviceId"
        type="hidden"
        value="15" />
    <div class="editor-label">
        <label for="DataGroups">Data groups</label>
    </div>
    <div class="editor-field">
        <select data-val="true"
            data-val-number="The field DataGroupsSelectedItem must be a number."
            id="DataGroupsSelectedItem"
            name="DataGroupsSelectedItem">
            <option value="2">DataGroup2</option>
            <option value="3">DataGroup3</option>
            <option value="5">New group</option>
        </select>
        <span class="field-validation-valid"
            data-valmsg-for="DataGroupsSelectedItem"
            data-valmsg-replace="true"></span>
    </div>
    <input type="submit" value="Assign Data Group" />
</form>

Answer 1

ID タグと値を追加する必要があります。