Question

目前，我正在使用XML来创建一个包含许多问题的数据结构，用于测验，其中包含问题本身，答案等信息，然后将这些问题放入要显示的变量中。标签。这是XML文件的一个示例：

<?xml version="1.0" encoding="utf-8"?>
<questionData>
    <question>
    <level> 1 </level>
    <ref> ref1 </ref>
    <questionText>This is a test question using XML!</questionText>
    <A>This is A using XML!</A>
    <B>This is B using XML!</B>
    <C>This is C using XML!</C>
    <D>This is D using XML!</D>
    <corrAnswer> A </corrAnswer>
    <APerc> 97 </APerc>
    <BPerc> 1 </BPerc>
    <CPerc> 1 </CPerc>
    <DPerc> 1 </DPerc>
    <PAFAnswer> A </PAFAnswer>
    <PAFFeeling> Sure </PAFFeeling>
    <FF> B </FF>
    <FFcorrPerc> 100 </FFcorrPerc>
    <FFwrongPerc> 0 </FFwrongPerc>
    <FFPAFAnswer> A </FFPAFAnswer>
    <FFPAFFeeling> Sure </FFPAFFeeling>
    <EXP> This is a test explanation for the info box. </EXP>
    <pronuns> pro-nun-cee-a-sh-un </pronuns>
    </question>

    <question>
    <level> 2 </level>
    <ref> ref2 </ref>
    <questionText>This is another test question using XML!</questionText>
    <A>This is A2 using XML!</A>
    <B>This is B2 using XML!</B>
    <C>This is C2 using XML!</C>
    <D>This is D2 using XML!</D>
    <corrAnswer> B </corrAnswer>
    <APerc> 96 </APerc>
    <BPerc> 1 </BPerc>
    <CPerc> 1 </CPerc>
    <DPerc> 2 </DPerc>
    <PAFAnswer> B </PAFAnswer>
    <PAFFeeling> Sure </PAFFeeling>
    <FF> A </FF>
    <FFcorrPerc> 100 </FFcorrPerc>
    <FFwrongPerc> 0 </FFwrongPerc>
    <FFPAFAnswer> B </FFPAFAnswer>
    <FFPAFFeeling> Sure </FFPAFFeeling>
    <EXP> This is another test explanation for the info box. </EXP>
    <pronuns> pro-nun-cee-a-sh-un two </pronuns>
    </question>
</questionData>

现在，我打算在此文件中包含大量问题。然而，你进步的测验越进一步，他们就越难获得，因此我添加了一个名为level的元素，其数字对应于何时被询问（例如，你在测验中有15个问题，你有问题3因此它解析XML文件以获得level元素为3的问题，然后将数据加载到程序中。

然而，存在一个问题 - 很可能是逻辑错误。在C ++ / CLI代码中，我有：

         XmlTextReader^ dataFromQFile = gcnew XmlTextReader("Millionaire\\questionsData.xml");
         XmlDocument^ questionsData = gcnew XmlDocument();
         questionsData->Load("Millionaire\\questionsData.xml");
         XmlElement^ root = questionsData->DocumentElement;
         XmlNodeList^ listOfQuestions = root->GetElementsByTagName("questionData");
         XmlNodeList^ Questions = root->GetElementsByTagName("question");

         for each (Questions in listOfQuestions)
         {
             levelFromXML = (root->GetElementsByTagName("level"))->Item(0)->InnerText;
             questionFromXML = (root->GetElementsByTagName("questionText"))->Item(0)->InnerText;
             AFromXML = (root->GetElementsByTagName("A"))->Item(0)->InnerText;
             BFromXML = (root->GetElementsByTagName("B"))->Item(0)->InnerText;
             CFromXML = (root->GetElementsByTagName("C"))->Item(0)->InnerText;
             DFromXML = (root->GetElementsByTagName("D"))->Item(0)->InnerText;
             corrFromXML = (root->GetElementsByTagName("corrAnswer"))->Item(0)->InnerText;
             APercFromXML = (root->GetElementsByTagName("APerc"))->Item(0)->InnerText;
             BPercFromXML = (root->GetElementsByTagName("BPerc"))->Item(0)->InnerText;
             CPercFromXML = (root->GetElementsByTagName("CPerc"))->Item(0)->InnerText;
             DPercFromXML = (root->GetElementsByTagName("DPerc"))->Item(0)->InnerText;
             phoneAnswerFromXML = (root->GetElementsByTagName("PAFAnswer"))->Item(0)->InnerText;
             phoneFeelingFromXML = (root->GetElementsByTagName("PAFFeeling"))->Item(0)->InnerText;
             fiftyAnswer = (root->GetElementsByTagName("FF"))->Item(0)->InnerText;
             fiftyCorrPerc = (root->GetElementsByTagName("FFcorrPerc"))->Item(0)->InnerText;
             fiftyWrongPerc = (root->GetElementsByTagName("FFwrongPerc"))->Item(0)->InnerText;
             fiftyPhoneAnswer = (root->GetElementsByTagName("FFPAFAnswer"))->Item(0)->InnerText;
             fiftyPhoneFeeling = (root->GetElementsByTagName("FFPAFFeeling"))->Item(0)->InnerText;
             exp = (root->GetElementsByTagName("EXP"))->Item(0)->InnerText;
             pronuns = (root->GetElementsByTagName("pronuns"))->Item(0)->InnerText;
         }

当我尝试遍历问题列表时（questionData是父项，问题是孩子，问题包含的所有数据都是子项），当我尝试在标签中显示变量时，我得不到任何文本因此，让我相信我在循环中犯了一个逻辑错误。我对XML比较新，所以我无法发现错误。您是否有人能够帮助我或者可能知道更有效的方式来执行上述任务？感谢。

Answer 1

您的根元素（分别是documentElement）已经是questionData元素，因此执行root->GetElementsByTagName("questionData")会返回一个空列表。如果你想在循环中处理question元素，那么只需处理for each(question in questionsData->GetElementsByTagName("question"))然后在循环内部确保你在循环变量上调用方法，例如levelFromXML = (question->GetElementsByTagName("level"))->Item(0)->InnerText;。

我还会在循环中使用https://msdn.microsoft.com/en-us/library/sss31aas%28v=vs.110%29.aspx?cs-save-lang=1&cs-lang=cpp#code-snippet-1而不是GetElementsByTagName，因此您只需使用levelFromXML = question["level"]->InnerText;替换上述代码段。

XML循环遍历C ++ / CLI

1 个答案: