variable=字典中的类在使用后重置/清除var

我对Var"item"有问题，我从xml循环中调用Method MyItems，并按键从Dictionary中选择类，出于某种原因，数量是正确的，但它们都来自相同的类型/值/图标。。。。。

添加到_list.Add（item）后，我如何重置、清除、null或其他任何"项"。。。。c#新手。。。。。。

*我希望我的邮政编码/格式现在是正确的：p

public class ISwitch : Form1
{
    private static Dictionary<int, Base> _objectsToList;
    private static bool _dicSet = false;
    // Build Dictionary 
    static ISwitch()
    {
        Debug.Write("-----------------------------------------------------'n");
        Debug.Write("dic created'n");
        _objectsToList = new Dictionary<int, SenseItemBase>
                             {
                                 {1, new Control()},
                                 {2, new Control2()},
                                 {3, new MoreItems()},
                                 {4, new MoreItems2()}
                             };
        _dicSet = true;
    }
    public static void MyItems(int id, int funcid, string _index, string _text, string icongfx, string property, string type, string _function, string _itemtype)
    {
        if (!_dicSet) return;
        Debug.Write("-----------------------------------------------------'n");
        Debug.Write("ID : " + id + "'n");
        Debug.Write("funcid : " + funcid + "'n");
        Debug.Write("Case : " + _index + "'n");
        Debug.Write("Property : " + property + "'n");
        Debug.Write("Type : " + type + "'n");
        Debug.Write("Function : " + _function + "'n");
        Debug.Write("Icon : " + icongfx + "'n");
        Debug.Write("Text : " + _text + "'n");
        Debug.Write("Switch : " + _itemtype + "'n");
        XFItemStyle Style;
        switch (id)
        {
            case 1:
                if (_objectsToList.ContainsKey(funcid))
                {
                    var item = _objectsToList[funcid];
                    Debug.Write("-----------------------------------------------------'n");
                    Debug.Write("- Item-'n");
                    Debug.Write("_objectsToList : " + item + "'n");
                    Debug.Write("ID : " + id + "'n");
                    Debug.Write("funcid : " + funcid + "'n");
                    item.Style = IStyle.MyStyle(_index, "HelveticaNeue", "HelveticaNeue", out Style);
                    item.MainText = _text;
                    item.myIcon = Path + "''" + icongfx;
                    _list.Add(item);
                }
                return;
            case 2:
                if (_objectsToList.ContainsKey(funcid))
                {
                    var item = _objectsToList[funcid];
                    Debug.Write("-----------------------------------------------------'n");
                    Debug.Write("- Item action-'n");
                    Debug.Write("_objectsToList : " + item + "'n");
                    Debug.Write("ID : " + id + "'n");
                    item.Style = IStyle.MyStyle(_index, "HelveticaNeue", "HelveticaNeue", out Style);
                    item.MainText = _text;
                    item.SecondaryText = _text;
                    item.myIcon = Path + "''" + icongfx;
                    _list.Add(item);
                    item = null;
                }
                return;
        }
    }
}

感谢

_objectToList.Remove(funcid);