const char* const XmlTag = "<?xml version=\"1.0\"?>\r\n";
 CMarkup tempXml;
 tempXml.AddElem("Item");
 tempXml.AddChildElem("ItemId",111);
 tempXml.AddChildElem("ItemName","My111");

 CMarkup xmlDoc(XmlTag);
 xmlDoc.AddElem("Response");
 xmlDoc.AddChildElem("CmdType","Catalog");
 xmlDoc.AddChildElem("DeviceList");
 xmlDoc.SetChildAttrib("Num",2);
 xmlDoc.IntoElem();
  xmlDoc.AddChildElem("Item");
  xmlDoc.IntoElem();
   xmlDoc.AddChildElem("ItemId",1);
   xmlDoc.AddChildElem("ItemName","Name");
  xmlDoc.OutOfElem();

  xmlDoc.AddChildElem("Item");
  xmlDoc.IntoElem();
   xmlDoc.AddChildElem("ItemId",2);
   xmlDoc.AddChildElem("ItemName","Name2");
  xmlDoc.OutOfElem();

  xmlDoc.AddChildSubDoc(tempXml.GetDoc());
 xmlDoc.OutOfElem();

产生的xml数据格式如下

<?xml version="1.0"?>
<Response>
    <CmdType>Catalog</CmdType>
    <DeviceList Num="2">
        <Item>
            <ItemId>1</ItemId>
            <ItemName>Name</ItemName>
       </Item>
       <Item>
           <ItemId>2</ItemId>
           <ItemName>Name2</ItemName>
      </Item>
      <Item>
          <ItemId>111</ItemId>
          <ItemName>My111</ItemName>
     </Item>
 </DeviceList>
</Response>