MFC操作XML（转载）

MFC
MFC里可以直接使用DOM，不需要手动添加额外的头文件，只需要在CWinApp::InitInstance()里调用CoInitialize(NULL)初始化COM，在CWinApp::ExitInstance里调用CoUninitialize()释放COM就行了。

//读取XML
CComPtr<IXMLDOMDocument> spDoc; //DOM
spDoc.CoCreateInstance(CLSID_DOMDocument);
VARIANT_BOOL vb;
spDoc->load(CComVariant(OLESTR("xmlfile.xml")), &vb); //加载XML文件
CComPtr<IXMLDOMElement> spRootEle;
spDoc->get_documentElement(&spRootEle); //根节点
CComPtr<IXMLDOMNodeList> spNodeList;
spRootEle->get_childNodes(&spNodeList); //子节点列表
long nLen;
spNodeList->get_length(&nLen); //子节点数
for (long i = 0; i != nLen; ++i) //遍历子节点
{
CComPtr<IXMLDOMNode> spNode;
spNodeList->get_item(i, &spNode);
ProcessNode(spNode); //节点处理函数
}

//写入XML
CComPtr<IXMLDOMNode> spNode;
spRootEle->selectSingleNode(OLESTR("/root/node1"), &spNode);
spNode->put_text(OLESTR("newText")); //写入text
spRootEle->selectSingleNode(OLESTR("/root/node2/childnode1/@attrib1"), &spNode);
spNode->put_nodeValue(CComVariant(OLESTR("newValue"))); //写入value
CComPtr<IXMLDOMNode> spNewNode;
spDoc->createNode(CComVariant(NODE_ELEMENT), OLESTR("childnode3"), OLESTR(""), &spNewNode); //创建新节点
spRootEle->selectSingleNode(OLESTR("/root/node2"), &spNode);
spNode->appendChild(spNewNode, &spNewNode); //将新节点加为node2的子节点
spNewNode->put_text(OLESTR("childtext2")); //写入新节点text
CComQIPtr<IXMLDOMElement> spEle = spNewNode; //注意这里使用CComQIPtr
spEle->setAttribute(OLESTR("attrib1"), CComVariant(OLESTR("value1")));//给新节点添加属性
spDoc->save(CComVariant(OLESTR("stocks.xml")));

//节点处理函数
void ProcessNode(CComPtr<IXMLDOMNode>& spNode)
{
CComBSTR bsNodeName;
spNode->get_nodeName(&bsNodeName); //节点名
AfxMessageBox(COLE2CT(bsNodeName));
CComVariant varVal;
spNode->get_nodeValue(&varVal); //节点值
AfxMessageBox(COLE2CT(varVal.bstrVal));

DOMNodeType eNodeType;
spNode->get_nodeType(&eNodeType);
if (eNodeType == NODE_ELEMENT) //只有NODE_ELEMENT类型才能包含有属性和子节点
{
//递归遍历节点属性
CComPtr<IXMLDOMNamedNodeMap> spNameNodeMap;
spNode->get_attributes(&spNameNodeMap);
long nLength;
spNameNodeMap->get_length(&nLength);
for (long i = 0; i != nLength; ++i)
{
CComPtr<IXMLDOMNode> spNodeAttrib; //注意属性也是一个IXMLDOMNode
spNameNodeMap->get_item(i, &spNodeAttrib);
ProcessNode(spNodeAttrib);
}

//递归遍历子节点
CComPtr<IXMLDOMNodeList> spNodeList;
spNode->get_childNodes(&spNodeList);
spNodeList->get_length(&nLength);
for (long i = 0; i != nLength; ++i)
{
CComPtr<IXMLDOMNode> spChildNode;
spNodeList->get_item(i, &spChildNode);
ProcessNode(spChildNode);
}
}
}