Question

我在课程中定义了typedef std::vector<ColorInfo*> ColorInfoVector;

struct ColorInfo
{
    ColorInfo() : m_displayVector() {}


    // data members 
    DisplayAttrVector m_displayVector;
};

我在方法中获得输入

void Display (ColorInfoVector                     *colorInfoVector)

在我尝试访问成员变量时的方法，如下面的结构

DisplayAttrVector dispAttrs = (*(colorInfoVector[i]))->m_displayVector;

得到错误

error C2100: illegal indirection
error C2039: 'm_displayVector': is not a member of 'std::vector<ColorInfo *>'

Answer 1

应该像这样工作：

// Gets your config section. It won't parse the xml to a 
// key/value structure, but does provide the raw xml
var b = config.GetSection("AutoUpdate/Settings"); 

var rawXml = b.SectionInformation.GetRawXml();

// Get the raw xml value and load it to a queryable XDocument object
var doc = XDocument.Parse(rawXml);
doc.Descendants("add")
    .Single(x => x.Attribute("key").Value == "ServerUrl")
    .SetAttributeValue("value", "http://newthing.xml");

// Set the new xml back to the configuration object and persist the changes
b.SectionInformation.SetRawXml(doc.ToString());
config.Save(ConfigurationSaveMode.Modified, true);

Answer 2

排队

DisplayAttrVector dispAttrs = (*((*colorInfoVector)[i]))->m_displayVector;

(*colorInfoVector)[i]给你一个指针。要使用指针访问结构的成员，您需要编写

((*colorInfoVector)[i])->m_displayVector

或

(*((*colorInfoVector)[i]))).m_displayVector

两者都做同样的事情。

如何访问结构的成员

2 个答案: