TinyXML2庫的簡單使用

1.創(chuàng)建XML

//xml頭部聲明

const char* declaration ="<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>";

//XML文檔對象

XMLDocument doc;

//插入頭部聲明，會覆蓋xml所有內(nèi)容

doc.Parse(declaration);

//下面方法也能插入頭部聲明泪喊，但是不會覆蓋

XMLDeclaration* declaration=doc.NewDeclaration();

doc.InsertFirstChild(declaration);

//創(chuàng)建一個節(jié)點--根節(jié)點

XMLElement* root=doc.NewElement("config");

//將根節(jié)點插入xml文檔

doc.InsertEndChild(root);

//創(chuàng)建并保存到指定路徑

doc.SaveFile(xmlPath);

//讀取一個存在的xml

doc.LoadFile(xmlPath);

//創(chuàng)建一個節(jié)點對象User

XMLElement *userNode = doc.NewElement("User");

//給生成的節(jié)點對象添加屬性

userNode->SetAttribute("Name", user.userName.c_str());

//把User節(jié)點插入到root節(jié)點下

root->InsertEndChild(userNode);

//創(chuàng)建一個Gender節(jié)點

XMLElement* gender = doc.NewElement("Gender");

//創(chuàng)建一個Text文本對象genderText

XMLText* genderText=doc.NewText(itoa(user.gender));

//將文本對象加入到Gender節(jié)點下

gender->InsertEndChild(genderText);

//把Gender節(jié)點插入到userNode節(jié)點下

userNode->InsertEndChild(gender);

//保存節(jié)點到文件中

doc.SaveFile(xmlPath);

//修改userNode節(jié)點下的Password屬性為user->password.c_str()

userNode->SetAttribute("Password",user->password.c_str()); 

//修改mobileNode節(jié)點的內(nèi)容為user->mobile.c_str()

mobileNode->SetText(user->mobile.c_str());

2.讀取XML

//獲取文檔對象的根節(jié)點

XMLElement* root=doc.RootElement();

//獲取到root節(jié)點的子節(jié)點User

XMLElement* userNode=root->FirstChildElement("User");

//獲取到子節(jié)點的Name屬性

userNode->Attribute("Name");

//獲取下一個兄弟節(jié)點

userNode=userNode->NextSiblingElement();

//獲取userNode節(jié)點下名為Gender的子節(jié)點

XMLElement* genderNode=userNode->FirstChildElement("Gender");

//獲取genderNode節(jié)點的文本內(nèi)容

genderNode->GetText();

//將xml打印至控制臺

doc.Print();

//將XML輸出至內(nèi)存

XMLPrinter printer;

doc.Print( &printer );

使用

int ReadXML(const char* xmlPath)
{   //聲明XML文檔
    tinyxml2::XMLDocument doc;
    //加載文檔
    int ret = doc.LoadFile(xmlPath);
    if (ret != tinyxml2::XML_SUCCESS)
    {
        fprintf(stderr,"LoadFile failed");
        return doc.ErrorID();
    }
    //讀取根節(jié)點
    tinyxml2::XMLElement* root = doc.RootElement();
    if(root == nullptr)
    {
        fprintf(stderr,"read root node failed");
        return doc.ErrorID();
    }
    struct ServerAddr
    {
        int index;
        std::string ip;
        unsigned short port;
    };
    ServerAddr server_addr;
    //讀取根節(jié)點的子節(jié)點
    tinyxml2::XMLElement* server_addr_node = XMLNodeGetChildNode(root,"server_addr");
    
    ret = ReadXMLIntNode(XMLNodeGetChildNode(server_addr_node,"Index"),server_addr.index);//讀取int   
    if(ret != 0)
    {
        //todo:錯誤處理+日志打印
    }
    ret = ReadXMLStringNode(XMLNodeGetChildNode(server_addr_node,"Ip"),server_addr.ip); //讀取string
    if(ret!= 0)
    {
        //todo:錯誤處理+日志打印
    }
    ret = ReadXMLUShortNode(XMLNodeGetChildNode(server_addr_node,"Port"),server_addr.port); //讀取ushort
    if(ret!= 0)
    {
        //todo:錯誤處理+日志打印
    }

    fprintf(stdout,"index =%d ,ip = %s ,port = %d\n",server_addr.index,server_addr.ip,server_addr.port);
    doc.Print();
    return doc.ErrorID();
}
//讀取字符串類型節(jié)點
int ReadXMLStringNode(tinyxml2::XMLElement* node,std::string& dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    const char* data = node->GetText();
    dst = data;
    return tinyxml2::XML_SUCCESS;
}
//讀取字符串類型節(jié)點
int ReadXMLStringNode(tinyxml2::XMLElement* node,char * dst,int size)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    const char* data = node->GetText();
    assert(sizeof(data) <= size);
    memcpy(dst,data,size);
    return tinyxml2::XML_SUCCESS;
}
//讀取int值類型節(jié)點
int ReadXMLIntNode(tinyxml2::XMLElement* node,int & dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    dst = node->IntText();
    return tinyxml2::XML_SUCCESS;
}
//讀取double值類型節(jié)點
int ReadXMLDoubleNode(tinyxml2::XMLElement* node,double & dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    dst = node->DoubleText();
    return tinyxml2::XML_SUCCESS;
}
//讀取浮點值類型節(jié)點
int ReadXMLFloatNode(tinyxml2::XMLElement* node,float & dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    dst = node->FloatText();
    return tinyxml2::XML_SUCCESS;
}
//讀取longlong類行值節(jié)點
int ReadXMLInt64Node(tinyxml2::XMLElement* node,long long & dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    dst = node->Int64Text();
    return tinyxml2::XML_SUCCESS;
}
//讀取 unsigned long long類行值節(jié)點
int ReadXMLUInt64Node(tinyxml2::XMLElement* node,unsigned long long & dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    dst = node->Unsigned64Text();
    return tinyxml2::XML_SUCCESS;
}
//讀取bool值節(jié)點
int ReadXMLBoolNode(tinyxml2::XMLElement* node,bool & dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    dst = node->BoolText();
    return tinyxml2::XML_SUCCESS;
}
//讀取short值節(jié)點
int ReadXMLUShortNode(tinyxml2::XMLElement* node,unsigned short & dst)
{
    if(nullptr == node)
    {
        return tinyxml2::XML_NO_TEXT_NODE;
    }
    dst = node->UnsignedText();
    return tinyxml2::XML_SUCCESS;
}


tinyxml2::XMLElement* XMLNodeGetChildNode(tinyxml2::XMLElement* father_node,const char* name,int *errornum)
{
    if(father_node == nullptr)
    {
        *errornum = tinyxml2::XML_ERROR_FILE_READ_ERROR;
        return nullptr;
    }
    return father_node->FirstChildElement(name);
    *errornum = tinyxml2::XML_SUCCESS;
}