blocks|key|4529780|text|我想通了：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4529781|QStringList+propertyNames;
QStringList+propertyKeys;
QString+strReply+=+(QString)reply->readAll();
QJsonDocument+jsonResponse+=+QJsonDocument::fromJson(strReply.toUtf8());
QJsonObject+jsonObject+=+jsonResponse.object();
QJsonArray+jsonArray+=+jsonObject["properties"].toArray();

foreach+(const+QJsonValue+&+value,+jsonArray)+{
++++QJsonObject+obj+=+value.toObject();
++++propertyNames.append(obj["PropertyName"].toString());
++++propertyKeys.append(obj["key"].toString());
}|code-block|syntax|javascript|4529782|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I figured it out:

<pre><code>QStringList propertyNames;
QStringList propertyKeys;
QString strReply = (QString)reply-&gt;readAll();
QJsonDocument jsonResponse = QJsonDocument::fromJson(strReply.toUtf8());
QJsonObject jsonObject = jsonResponse.object();
QJsonArray jsonArray = jsonObject["properties"].toArray();

foreach (const QJsonValue &amp; value, jsonArray) {
 QJsonObject obj = value.toObject();
 propertyNames.append(obj["PropertyName"].toString());
 propertyKeys.append(obj["key"].toString());
}
</code></pre>

blocks|key|1704102|text|这里有一个来自How+To+Manipulate+JSON+With+C%2B%2B+and+Qt的例子。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1704103|//+reads+a+json+file+from+disk+to+QVariantMap
//+originally+from+http://erickveil.github.io/2016/04/06/How-To-Manipulate-JSON-With-C%2B%2B-and-Qt.html
bool+readJsonFile(std::string+file_path,+QVariantMap&+result)
{
++++//+step+1
++++QFile+file_obj(QString::fromStdString(file_path));
++++if+(!file_obj.open(QIODevice::ReadOnly))+{
++++std::cout+<<+"Failed+to+open+"+<<+file_path+<<+std::endl;
++++exit(1);
++++}

++++//+step+2
++++QTextStream+file_text(&file_obj);
++++QString+json_string;
++++json_string+=+file_text.readAll();
++++file_obj.close();
++++QByteArray+json_bytes+=+json_string.toLocal8Bit();

++++//+step+3
++++auto+json_doc+=+QJsonDocument::fromJson(json_bytes);

++++if+(json_doc.isNull())+{
++++++++std::cout+<<+"Failed+to+create+JSON+doc."+<<+std::endl;
++++++++return+false;
++++}
++++if+(!json_doc.isObject())+{
++++++++std::cout+<<+"JSON+is+not+an+object."+<<+std::endl;
++++++++return+false;
++++}

++++QJsonObject+json_obj+=+json_doc.object();

++++if+(json_obj.isEmpty())+{
++++++++std::cout+<<+"JSON+object+is+empty."+<<+std::endl;
++++++++return+false;
++++}

++++//+step+4
++++result+=+json_obj.toVariantMap();
++++return+true;
}

//+writes+a+QVariantMap+to+disk
bool+writeJsonFile(QVariantMap+point_map,+std::string+file_path)
{
++++QJsonObject+json_obj+=+QJsonObject::fromVariantMap(point_map);
++++QJsonDocument+json_doc(json_obj);
++++QString+json_string+=+json_doc.toJson();

++++QFile+save_file(QString::fromStdString(file_path));
++++if+(!save_file.open(QIODevice::WriteOnly))+{
++++++++std::cout+<<+"failed+to+open+save+file"+<<+std::endl;
++++++++return+false;
++++}
++++save_file.write(json_string.toLocal8Bit());
++++save_file.close();
++++return+true;
}|code-block|syntax|javascript|1704104|entityMap|0|LINK|mutability|MUTABLE|url|http://erickveil.github.io/2016/04/06/How-To-Manipulate-JSON-With-C%2B%2B-and-Qt.html^0|7|12|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

Here is an example from 
<a href="http://erickveil.github.io/2016/04/06/How-To-Manipulate-JSON-With-C++-and-Qt.html" rel="noreferrer">How To Manipulate JSON With C++ and Qt</a>.

<pre><code>// reads a json file from disk to QVariantMap
// originally from http://erickveil.github.io/2016/04/06/How-To-Manipulate-JSON-With-C++-and-Qt.html
bool readJsonFile(std::string file_path, QVariantMap&amp; result)
{
 // step 1
 QFile file_obj(QString::fromStdString(file_path));
 if (!file_obj.open(QIODevice::ReadOnly)) {
 std::cout &lt;&lt; "Failed to open " &lt;&lt; file_path &lt;&lt; std::endl;
 exit(1);
 }

 // step 2
 QTextStream file_text(&amp;file_obj);
 QString json_string;
 json_string = file_text.readAll();
 file_obj.close();
 QByteArray json_bytes = json_string.toLocal8Bit();

 // step 3
 auto json_doc = QJsonDocument::fromJson(json_bytes);

 if (json_doc.isNull()) {
 std::cout &lt;&lt; "Failed to create JSON doc." &lt;&lt; std::endl;
 return false;
 }
 if (!json_doc.isObject()) {
 std::cout &lt;&lt; "JSON is not an object." &lt;&lt; std::endl;
 return false;
 }

 QJsonObject json_obj = json_doc.object();

 if (json_obj.isEmpty()) {
 std::cout &lt;&lt; "JSON object is empty." &lt;&lt; std::endl;
 return false;
 }

 // step 4
 result = json_obj.toVariantMap();
 return true;
}

// writes a QVariantMap to disk
bool writeJsonFile(QVariantMap point_map, std::string file_path)
{
 QJsonObject json_obj = QJsonObject::fromVariantMap(point_map);
 QJsonDocument json_doc(json_obj);
 QString json_string = json_doc.toJson();

 QFile save_file(QString::fromStdString(file_path));
 if (!save_file.open(QIODevice::WriteOnly)) {
 std::cout &lt;&lt; "failed to open save file" &lt;&lt; std::endl;
 return false;
 }
 save_file.write(json_string.toLocal8Bit());
 save_file.close();
 return true;
}
</code></pre>

blocks|key|5998595|text|我使用QT网络向Firebase发出API请求，但由于某种原因，我收到了一个充满数据的响应，但当解析到一个数组时，我收到了null。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5998596|void+firebaseHandler::parseResponse(const+QString+&response){
++++@TODO+for+some+reason+sometimes+the+arrayData+is+empty+

++++QJsonDocument+jsonDocument+=+QJsonDocument::fromJson(response.toUtf8());
++++QJsonValue+kind+=++jsonDocument.object().value("kind");
++++QJsonArray+arrayData+=+jsonDocument.array();

+++++qDebug()+<<+"json+response+is+"+<<+jsonDocument.toJson();
}|code-block|syntax|javascript|5998597|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I'm using QT Network for my API request to Firebase
but for some reason, I received a response full of data but when parsing to an array I received null.
<pre><code>void firebaseHandler::parseResponse(const QString &amp;response){
 @TODO for some reason sometimes the arrayData is empty 

 QJsonDocument jsonDocument = QJsonDocument::fromJson(response.toUtf8());
 QJsonValue kind = jsonDocument.object().value(&quot;kind&quot;);
 QJsonArray arrayData = jsonDocument.array();

 qDebug() &lt;&lt; &quot;json response is &quot; &lt;&lt; jsonDocument.toJson();
}
</code></pre>

I'm using Qt5. I am trying to obtain values from a json object. Here is what the json object looks like that I am trying to get data from:

<pre><code>{
 "success": true,
 "properties": [
 {
 "ID": 1001,
 "PropertyName": "McDonalds",
 "key": "00112233445566778899aabbccddeeff"
 },
 {
 "ID": 1002,
 "PropertyName": "Burger King",
 "key": "10112233445566778899aabbccddeeff"
 },
 {
 "ID": 1003,
 "PropertyName": "Taco Bell",
 "key": "20112233445566778899aabbccddeeff"
 }
 ]
}
</code></pre>

How can I create three arrays that contain <code>properties[x].ID</code>, <code>properties[x].PropertyName</code>, and <code>properties[x].key</code> in Qt?

Edit:

Using <code>QScriptEngine</code> I tried this:

<pre><code>QString data = (QString)reply-&gt;readAll();

QScriptEngine engine;

QScriptValue result = engine.evaluate(data);

qDebug() &lt;&lt; result.toString();
</code></pre>

Debug is saying "SyntaxError: Parse error"

Qt parsing JSON using QJsonDocument, QJsonObject, QJsonArray

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我使用的是Qt5。我正在尝试从json对象获取值。下面是我试图从中获取数据的json对象的样子：{    "success": true,    "properties": [        {            "ID": 1001,            "PropertyName": "McDonalds",...

问Qt使用QJsonDocument、QJsonObject、QJsonArray解析JSON
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