XML - 定位节点属性，推入 Flash AS3 数组

Question

我试图将每个“question”标记中的“txt”属性的内容推送到 AS3 Flash 中名为“questions”的数组中。这是我的 xml 文件的摘录。

<question id='Q1' uId='99036'  no_ans='2' txt='In a flat structure employees are not expected to provide their bosses with their opinions.' feedback='' type='MC' passingWeight='1' url='media/'>
    <answer id='Q1A1' uId='311288' txt='True' weight='0'/>
    <answer id='Q1A2' uId='311289' txt='False' weight='1'/>
</question>
<question id='Q2' uId='99037'  no_ans='2' txt='In a hierarchy, information typically flows downward.' feedback='' type='MC' passingWeight='1' url='media/'>
    <answer id='Q2A1' uId='311290' txt='True' weight='1'/>
    <answer id='Q2A2' uId='311291' txt='False' weight='0'/>
</question>
<question id='Q3' uId='99038'  no_ans='2' txt='Someone who keeps many projects going at one time is an example of someone who is flexible-time oriented.' feedback='' type='MC' passingWeight='1' url='media/'>
    <answer id='Q3A1' uId='311292' txt='True' weight='1'/>
    <answer id='Q3A2' uId='311293' txt='False' weight='0'/>
</question>

这是我的循环尝试：

// get number of questions
    trace(myXML.question.length());
    numberOfQuestions = myXML.question.length();

    //loop and push questions into questions array at top
    for (var i:int = 0; i < numberOfQuestions; i++) {
        trace("Hello.");
        questions.push(myXML.question.@txt);
        trace(questions);
    }

这只是将所有 9 个问题一次推送到数组的每个位置。我想要每个数组位置 1 个问题。我不确定如何使用问题标签中的 id 属性来区分每个问题。

编辑： 我试过了，我可以使用 getQuestionAt(2) 从 processXML 函数内部访问问题文本，但不能在外部。

var myXML:XML;
var myLoader:URLLoader = new URLLoader();
myLoader.load(new URLRequest("html/VUBZ7318CROSSCULTUREQUIZ/manifest.xml"));
myLoader.addEventListener(Event.COMPLETE, processXML);
function processXML(e:Event):void {
    myXML = new XML(e.target.data);

    //trace(myXML.question)

    // get number of questions
    trace(myXML.question.length());
    numberOfQuestions = myXML.question.length();

    //Question list
    var questions:Object = {};
    //Extracting question from xml
    for each (var item:XML in myXML.question) {
        questions[item. @ id] = item. @ txt;
    }
    //Some method for fetching question from question list
    function getQuestionAt( index:Number ):String {
        if (questions["Q" + index] == undefined) {
            throw new Error("Wrong index for question!!!");
        }
        return questions["Q"+index];
    }

    //Getting question from list
    trace( "Here is question No 2:\t" + getQuestionAt(2) );


}

Answer 1

创建只有一帧的新图层，并使该帧的长度与您的总帧数一样长（例如 6 帧）。然后将此代码放入该框架中。

//Question list
var questions:Object; 
//Some method for fetching question from question list
function getQuestionAt( index:Number ):String{
    if( questions["Q"+index] == undefined ){
        throw new Error("Wrong index for question!!!");
    }
    return questions["Q"+index];
}    

然后将这些行添加到您的 processXML 函数中

function processXML():*{
 //.....Your 'myXML' is here....
 questions = {};
 //Extracting question from xml
 for each(var item:XML in myXML.question){
    questions[item.@id] = item.@txt;
 }
}   

如有任何问题，请致电getQuestionAt。您可以在任何帧中调用该函数，因为它在所有帧上都是“可见的”。

Answer 2

您的 XML 设置有点错误。在 AS3 中，您需要一个根节点。根节点不可访问，它只是一种包装器。在您的情况下，问题是您无法访问的根节点，这将使这些属性也无法访问。因此，在您的 xml 周围放置一个包装器。无法访问根节点属性可能是错误的，但是我对您的 XML 不正确是正确的。添加包装器让事情变得更简单。

<questions>
  <question id='Q1' uId='99036'  no_ans='2' txt='In a flat structure employees are not expected to provide their bosses with their opinions.' feedback='' type='MC' passingWeight='1' url='media/'>
      <answer id='Q1A1' uId='311288' txt='True' weight='0'/>
      <answer id='Q1A2' uId='311289' txt='False' weight='1'/>
  </question>
  <question id='Q2' uId='99037'  no_ans='2' txt='In a hierarchy, information typically flows downward.' feedback='' type='MC' passingWeight='1' url='media/'>
      <answer id='Q2A1' uId='311290' txt='True' weight='1'/>
      <answer id='Q2A2' uId='311291' txt='False' weight='0'/>
  </question>
  <question id='Q3' uId='99038'  no_ans='2' txt='Someone who keeps many projects going at one time is an example of someone who is flexible-time oriented.' feedback='' type='MC' passingWeight='1' url='media/'>
      <answer id='Q3A1' uId='311292' txt='True' weight='1'/>
      <answer id='Q3A2' uId='311293' txt='False' weight='0'/>
  </question>
</questions>

然后像这样抓取属性。

var questions:XMLList =  new XMLList( e.target.data.question )
for each ( var question:XML in questions){
  trace( question.@txt )
}

Answer 3

你拥有的不是 XML，而是一个 XMLList，完全可以接受。

你不需要循环。您可以像这样获得另一个 XMLList。 XMLList 就像一个 XML 数组，但在这种情况下，您不会有完全形成的节点，而只有所有属性的内容。

它会变成这样：

var questionTxt:XMLList = yourQuestions.@txt;//yourQuestions contains your originalXMLList as shown above

现在，您可以通过以下方式访问每个文本元素：

var stem:String = String(questionTxt[0]);

如果出于某种原因你绝对必须有一个数组，你可以这样做：

var questions:Array = new Array();
for (var i:int = 0; i< questionTxt.length(); i++) {
    questions[i] = questionTxt[i];
}

但是，看起来很多工作都是徒劳的，因为您可以通过 e4x 访问 XMLList 来简单地使用它。您的全部目标是什么？

我只是更仔细地看了你的问题，你真正需要做的就是：

protected var questions:XMLList;
public function processXML(e:Event):void {
            myXML = XML(e.target.data);
            questions = myXML.question;

            // get number of questions
            trace(myXML.question.length());
}

public function getQuestionAt( index:Number ):String {
            if (questions[index] == undefined) {
                throw new Error("Wrong index for question!!!");
            }
            return questions[index].attribute('txt');
}       

public function get numberOfQuestions():int {
    return myXML.question.length();
}