一.普通文件读写

1.写入文件（bool HelloWorld::init()里写入如下代码）

   FileUtils *fu=FileUtils::getInstance();
    FILE *f=fopen(fu->fullPathFromRelativeFile("data.txt",fu->getWritablePath()).c_str(),"w");
    fprintf(f,"Hello ws\n");
    fclose(f);
    log("%s",fu->getWritablePath().c_str());

    Data d=fu->getDataFromFile(fu->fullPathFromRelativeFile("data.txt",fu->getWritablePath()));
    log("%s",d.getBytes());

    UserDefault::getInstance()->setStringForKey("data","Hello ws");
    
    log("%s",UserDefault::getInstance()->getStringForKey("data1","Hello world").c_str());

二.读取plist文件

1.先在resource里创建plist文件

2.然后在HelloWorldScene.cpp的init()函数输入以下代码即可

    FileUtils *fu=FileUtils::getInstance();
    auto vm=fu->getValueMapFromFile("data.plist");//dictionary,如果是vector,使用fu->getValueVectorFromFile(const std::string &filename)
    
    log("%s",vm["name"].asString().c_str());
    log("%s",vm["arr"].asValueVector().at(1).asString().c_str());

三.读取xml文件

1.先在resource里创建xml文件，在里面输入

<data>
    <p name="ZhangSan" age="10" />
    <p name="LiSi" age="11" />
</data>

  auto doc =new tinyxml2::XMLDocument();
    doc->Parse(FileUtils::getInstance()->getStringFromFile("data.xml").c_str());
    
    auto root=doc->RootElement();
    for (auto e=root->FirstChildElement(); e; e=e->NextSiblingElement()) {
        std::string str;
        for (auto attr=e->FirstAttribute(); attr; attr=attr->Next()) {
            str+=attr->Name();
            str+=":";
            str+=attr->Value();
            str+=",";
        }
        log("%s",str.c_str());
    }