【求助】怎么打印或者转换double类型为字符串

void Main_OnCommand(HWND hwnd, int id, HWND hwndCtl, UINT codeNotify)
{
    switch(id)
    {
        case IDC_OK:
            {
                TCHAR r[256];
               

                GetDlgItemText(hwnd,IDC_EDITR,r,sizeof(r));

                int radius=atoi(r);
                double Area=3.141592653*radius*radius;

                TCHAR area[256];
                swprintf(

            }
        break;
        default:
        break;
    }
}