（28）Cocos2d-x xml解析

Cocos2d-x 已经加入了tinyxml2用于xml的解析。3.0版本位于external/tinyxml2下。2.x版本位于cocos2dx/support/tinyxml2下。

tinyxml2 Github地址：https://github.com/leethomason/tinyxml2

帮助文档地址：http://grinninglizard.com/tinyxml2docs/index.html

生成xml文档

1. 引入头文件

   #include "tinyxml2/tinyxml2.h"
   using namespace tinyxml2;

2. xml文档生成

   void  HelloWorld::makeXML(const char *fileName)
   {
   std::string filePath = FileUtils::getInstance()->getWritablePath() + fileName;
   
   XMLDocument *pDoc = new XMLDocument();
   
   //xml 声明（参数可选）
   XMLDeclaration *pDel = pDoc->NewDeclaration("xml version=\"1.0\" encoding=\"UTF-8\"");
   
   pDoc->LinkEndChild(pDel);
   
   //添加plist节点
   XMLElement *plistElement = pDoc->NewElement("plist");
   plistElement->SetAttribute("version", "1.0");
   pDoc->LinkEndChild(plistElement);
   
   XMLComment *commentElement = pDoc->NewComment("this is xml comment");
   plistElement->LinkEndChild(commentElement);
   
   //添加dic节点
   XMLElement *dicElement = pDoc->NewElement("dic");
   plistElement->LinkEndChild(dicElement);
   
   //添加key节点
   XMLElement *keyElement = pDoc->NewElement("key");
   keyElement->LinkEndChild(pDoc->NewText("Text"));
   dicElement->LinkEndChild(keyElement);
   
   XMLElement *arrayElement = pDoc->NewElement("array");
   dicElement->LinkEndChild(arrayElement);
   
   for (int i = 0; i<3; i++) {
       XMLElement *elm = pDoc->NewElement("name");
       elm->LinkEndChild(pDoc->NewText("Cocos2d-x"));
       arrayElement->LinkEndChild(elm);
   }
   
   pDoc->SaveFile(filePath.c_str());
   pDoc->Print();
   
   delete pDoc;
   }

3. 打印结果

   <?xml version="1.0" encoding="UTF-8"?>
   <plist version="1.0">
   <!--this is xml comment-->
   <dic>
       <key>Text</key>
       <array>
           <name>Cocos2d-x</name>
           <name>Cocos2d-x</name>
           <name>Cocos2d-x</name>
       </array>
   </dic>
   </plist>

上面代码使用tinyxml简单生成了一个xml文档。

解析xml

下面我们就来解析上面创建的xml文档

1. 引入头文件

   #include "tinyxml2/tinyxml2.h"
   using namespace tinyxml2;

2. xml解析

   
   void HelloWorld::parseXML(const char *fileName)
   {
   
   std::string filePath = FileUtils::getInstance()->getWritablePath() + fileName;
   XMLDocument *pDoc = new XMLDocument();
   XMLError errorId = pDoc->LoadFile(filePath.c_str());
   
   if (errorId != 0) {
       //xml格式错误
       return;
   }
   
   XMLElement *rootEle = pDoc->RootElement();
   
   //获取第一个节点属性
   const XMLAttribute *attribute = rootEle->FirstAttribute();
   //打印节点属性名和值
   log("attribute_name = %s,attribute_value = %s", attribute->Name(), attribute->Value());
   
   XMLElement *dicEle = rootEle->FirstChildElement("dic");
   XMLElement *keyEle = dicEle->FirstChildElement("key");
   if (keyEle) {
       log("keyEle Text= %s", keyEle->GetText());
   }
   
   XMLElement *arrayEle = keyEle->NextSiblingElement();
   XMLElement *childEle = arrayEle->FirstChildElement();
   while ( childEle ) {
       log("childEle Text= %s", childEle->GetText());
       childEle = childEle->NextSiblingElement();
   }
   
   delete pDoc;
   
   }

   在节点解析过程中，注意对获取到的节点进行判空处理。

3. 解析结果打印

   cocos2d: attribute_name = version,attribute_value = 1.0
   cocos2d: keyEle Text= Text
   cocos2d: childEle Text= Cocos2d-x
   cocos2d: childEle Text= Cocos2d-x
   cocos2d: childEle Text= Cocos2d-x

小结

上面的简单示例，演示了如何使用tinyxml进行xml文档生成和解析。更多详细的帮助请参考 tinyxml帮助文档http://grinninglizard.com/tinyxml2docs/index.html