以下编译通过：

 以下编译错误：

现在修改代码，正确通过测试。

 

 扩展应用 泛型Object.ToString()。

/// <summary>
/// 转换为字符串
/// </summary>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
/// 创建时间： 2022-12-18      最后一次修改时间：2022-12-20
template<class T>
_string DList<T>::ToString()const
{
    _string sResult;

    if ( typeid(T) == typeid(int) )
    {

        if (_Count == 0) return sResult;       
      

        if (_Count == 1)
        {
            sResult.add(_string::java_valueOf(*( (int*) (& (_First->Data)))));
        }

        DListNote<T>* dn = this->_First;
        while (dn != _Last)
        {
            int* pInt = (int*)&(dn->Data);
            sResult.add(_string::java_valueOf(*pInt));
            sResult.add(_t(','));

            dn = dn->Next;
        }

        sResult.add(_string::java_valueOf(*((int*)(&(_Last->Data)))));

    }
    else if (typeid(T) == typeid(double))
    {
        if (_Count == 0) return sResult;

        double* pd;

        if (_Count == 1)
        {
            pd = (double*)(&(_First->Data));

            sResult.add(_tostr(*pd));
        }

        DListNote<T>* dn = this->_First;
        while (dn != _Last)
        { 
            pd = (double*)&(dn->Data);
            sResult.add(_tostr(*pd));
            sResult.add(_t(','));

            dn = dn->Next;
        }
        pd = (double*)&(_Last->Data);
        sResult.add(_tostr(*pd));
    }
    else if (typeid(T) == typeid(_string))
    {
        if (_Count == 0) return sResult;


        _string* ps;

        if (_Count == 1)
        {
            ps = (_string*)(&_First->Data);

            sResult.add(*ps);
        }

        DListNote<T>* dn = this->_First;
        while (dn != _Last)
        {
            ps = (_string*)(&dn->Data);

            sResult.add(*ps);
            sResult.add(_t(','));

            dn = dn->Next;
        }
        ps = (_string*)(&_Last->Data);

        sResult.add(*ps);
    }
    else if(typeid(T) == typeid(Object_))
    {
        if (_Count == 0) return sResult;


        Object_* po;

        if (_Count == 1)
        {
            po = (Object_*)(&_First->Data);

            sResult.add((_string) (*po) );
        }

        DListNote<T>* dn = this->_First;
        while (dn != _Last)
        {
            po = (Object_*)(&dn->Data);

            sResult.add((_string)(*po));
            sResult.add(_t(','));

            dn = dn->Next;
        }
        po = (Object_*)(&_Last->Data);

        sResult.add((_string)(*po));
    }
    else
    {
        sResult.add(_t("数据类型是："));
        sResult.add(gs.s_UTF8String_to_TextW(typeid(T).name()));
        sResult.add(_t("，函数还未完成，或者你自己重写 ToString() 虚拟函数 ！"));
    }
   

    return sResult;
}