Qt QXmlstreamreader故障

我试图读取XML标记中的文本。我正在使用readelementtext（）函数，但它返回一个空的Qstring。我使用的代码如下

#include <QCoreApplication>
#include <QFile>
#include <QStringList>
#include <QTextStream>
#include <QXmlStreamReader>
#include <QXmlStreamWriter>
#include <QByteArray>
#include <iostream>
#include <ostream>
#include <QString>

class XmlStreamLint
{
public:
    Q_DECLARE_TR_FUNCTIONS(XmlStreamLint)
};

int main(int argc, char *argv[])
{
    enum ExitCode
    {
        Success,
        ParseFailure,
        ArgumentError,
        WriteError,
        FileFailure
    };

    QCoreApplication app(argc, argv);

    QTextStream errorStream(stderr);

    if (argc != 2)
    {
        errorStream << XmlStreamLint::tr(
                       "Usage: xmlstreamlint <path to XML file>\n");
        return ArgumentError;
    }

    QString inputFilePath(QCoreApplication::arguments().at(1));
    QFile inputFile(inputFilePath);

    if (!QFile::exists(inputFilePath))
    {
        errorStream << XmlStreamLint::tr(
                       "File %1 does not exist.\n").arg(inputFilePath);
        return FileFailure;

    } else if (!inputFile.open(QIODevice::ReadOnly|QIODevice::Text)) {
        errorStream << XmlStreamLint::tr(
                       "Failed to open file %1.\n").arg(inputFilePath);
        return FileFailure;
    }
    QString outputfilepath="/home/shakeel/xmlstreamlint/testing.xml";
    QFile outputFile(outputfilepath);
    //QFile outputFile;
    if (!outputFile.open(stdout, QIODevice::WriteOnly))
    {
        errorStream << XmlStreamLint::tr("Failed to open stdout.");
        return WriteError;
    }
    QByteArray array[20000];
    QByteArray *ptr;
    ptr=&array[0];
    QXmlStreamReader reader(&inputFile);
    //QXmlStreamWriter writer(&outputFile);
    QXmlStreamWriter writer(ptr);
    QString text,signal;
    int count=0;
    while (!reader.atEnd())
    {
        reader.readNext();

        if (reader.error())
        {
            errorStream << XmlStreamLint::tr(
                           "Error: %1 in file %2 at line %3, column %4.\n").arg(
                               reader.errorString(), inputFilePath,
                               QString::number(reader.lineNumber()),
                               QString::number(reader.columnNumber()));
            return ParseFailure;

        } else
            if (reader.isStartElement())
            {
                text = reader.name().toString();
                if(text.operator ==("TYPICAL_CYCLE_CHANNEL"))
                {
                           count=count+1;
                           signal=reader.readElementText();
                           writer.writeCurrentToken(reader);

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE ECG SYSTEM "mortara.dtd">
<!-- Generated by Mortara ELI Link 2.20 -->
<!-- Mortara Instrument, Inc. -->
<!-- Server Name - Unknown -->
  <ECG
    ACQUISITION_TIME="20070227033111"
    ROOM=""
    LOCATION=""
    COMMENT=""
    AGE="59"
    AGE_UNITS="Y"
    HEIGHT=""
    HEIGHT_UNITS="I"
    WEIGHT=""
    WEIGHT_UNITS="L"
    NUM_QRS="10"
    AVERAGE_RR="935"
    VENT_RATE="64"
    SEQUENCE_NUMBER="6"
  >
  <DEMOGRAPHIC_FIELD ID="1"  LABEL="Name:" VALUE="Asd" UNITS="" />
  <DEMOGRAPHIC_FIELD ID="7"  LABEL="FName:&amp;," VALUE="We" UNITS="" />
  <DEMOGRAPHIC_FIELD ID="2"  LABEL="ID&amp;ID:" VALUE="12" UNITS="" />
  <DEMOGRAPHIC_FIELD ID="16" LABEL="DOB:" VALUE="12/13/47" UNITS="" />
  <DEMOGRAPHIC_FIELD ID="3"  LABEL="Age&amp;yr" VALUE="59" UNITS="Y" />
  <DEMOGRAPHIC_FIELD ID="4"  LABEL="Sex" VALUE="Male" UNITS="" />
  <SITE
    ID="0"
  />
  <SUBJECT
    LAST_NAME="Asd"
    FIRST_NAME="We"
    GENDER="Male"
    ID="12"
  />
  <SOURCE
    TYPE="RESTING"
    MANUFACTURER="Mortara Instrument, Inc."
    MANUFACTURER_ID="10"
    MODEL="el250"
    ID="4"
    TRANSMISSION_TIME="20070414092347"
  />
    <AUTOMATIC_INTERPRETATION>
      <STATEMENT
        STATEMENT_NUMBER="1"
        TEXT="SINUS RHYTHM WITH SHORT PR INTERVAL"
        REASON=""
      />
      <STATEMENT
        STATEMENT_NUMBER="2"
        TEXT="TYPE A WOLFF-PARKINSON-WHITE PATTERN"
        REASON=""
      />
      <STATEMENT
        STATEMENT_NUMBER="3"
        TEXT="NO FURTHER INTERPRETATION POSSIBLE"
        REASON=""
      />
      <STATEMENT
        STATEMENT_NUMBER="4"
        TEXT="ATYPICAL ECG"
        REASON=""
      />
      <STATEMENT
        STATEMENT_NUMBER="5"
        TEXT=""
        REASON=""
      />
      <STATEMENT
        STATEMENT_NUMBER="6"
        TEXT="UNCONFIRMED REPORT"
        REASON=""
      />
    </AUTOMATIC_INTERPRETATION>
  <TYPICAL_CYCLE
    R_PEAK="500"
    P_ONSET="-185"
    P_OFFSET="-116"
    Q_ONSET="-87"
    Q_OFFSET="75"
    T_OFFSET="369"
    P_DURATION="69"
    PR_DURATION="98"
    QRS_DURATION="162"
    QT="456"
    QTC="465"
    QTCB="471"
    QTCF="466"
    P_AXIS="17"
    QRS_AXIS="-54"
    T_AXIS="108"
    BITS="16"
    FORMAT="SIGNED"
    UNITS_PER_MV="400"
    DURATION="1200"
    SAMPLE_FREQ="1000"
    ENCODING="BASE64"
  >
  <TYPICAL_CYCLE_CHANNEL
    NAME="I"
    DATA="BQAAAP7/AAAAAP7/AAACAAIAAgAAAP7//v/+/wAA/v8AAAIAAAAAAAIA/v/+
/wAAAAAAAAAAAAD+/wAAAAD7//v/AgACAAAA/v/+//v/+f/5//v/+f/7/wAA
AgACAP7/+//5//b/9P/0/wAA+/8AAAAA/v/7//T/8f/5//n//v/7//7/AgAA
AP7/AAD5//n//v/5//v/AAD7//n/AAAAAPv/+//7//7//v/5//v/+f/5//v/
+f/5//v/AAD7//n/+f/5//n/9v/2//T/+f/5//v/9v/+//n/+f/5//n/+f/+
//n/+f/5//n//v8AAPv/+f/7//n/+f/2//T//v/5//b/9v/0//v//v/5//b/
9v/0//T/9P/x//H/9P/7//7//v/2//n/+//5//n/9P/5//n/+//x//T/7//0
//b/8f/2//n/+//7/wAA9v/2//H/9P/0//T/7//x//n/9v/7/wAA+//5//b/
9v/2//b/9v/v//H/9v/0//n/+f/2//T/7//x//b/9v/0//b/+f/x//H/8f/0
//T/8f/5//n/9v/5//n/9v/2//b/+f/2//b/9v/+//n/9P/s//H/9P/2//H/
7//x//b/9v/0//T/9v/5//b/9P/2//T/+//+//H/7P/q/+//9P/v//H/9v/x
//H/9P/0//b/9v/5//T/+f/2//v/+//2//T/9P/2//b/9v/x//T/9v/2//H/
9P/5//b/8f/0//T/9v/0//H/7P/s/+z/9P/5//v/9v/5//b/9P/x/+//9v/x
//T/9v/2//T/9v/2//T/9P/0/+//8f/x//b/9P/x/+//8f/0//T/+f/+//v/
9v/0//v/AAD7//T/9v/5//v/+f/+/wIAAAD7//n//v/7/wIAAgAAAP7/AAAH
AAUAAAACAAcABwAUAAwAAgAAAP7/AAAKAAIABwAFAAcACgAPAAoADAARAAwA
CgAKAAwACgARAAwAEQARAA8ACgAKAAoACgARAAoACgAFAAcABwAAAAIABwAK
AAcABwAHAAUAAgAFAAIAAgAFAAUACgAKAAwACgAKAAwABwAFAAIABQACAAIA
AgAHAAIAAAAAAAAA+//7/wAA/v/+//7/AAAFAAAAAAAFAAIABQAKAAoAFAAW
ABkAGwAeACAAKAAtADQAPABDAE0AVQBQAFIAVQBVAFoAVwBSAFoAYQBkAGQA
ZABrAHAAbgBwAHMAdQB6AIIAhwCMAI4AlgCgAKUArACxALkAuwDAAMgAzQDU
ANwA3ADmAOsA9QD8AAEBAQEJARUBIgEsATsBRwFRAWABcgGBAZUBrgG/Ac4B
7AEAAhkCKwI3AksCXQJkAmwCbgJuAnYCewJ2AnMCbgJpAmcCXQJVAkYCPAIr
Ag8C9gHlAdsBxwGwAZoBgQFoAVEBQAEpARgBBgH3AOMAzQC5AKoAnQCMAHoA
ZABXAEgAQQA5AC0ALQAlACAAIAAbABsAFgAWAAIAAgAAAAcAAgD5//H/9P/x
//H/9v/v//b/8f/v/+z/6v/s//H/9v/0//H/6v/0//T/8f/v/+r/7P/s/+f/
5f/q/+r/7P/q/+r/5//q/+//7P/l/+X/5f/q/+X/2//g/+X/5//l/+L/4P/g
/+r/7P/s/+f/5f/l/+X/5f/l/+f/6v/l/+X/5f/q/+z/6v/s/+r/5//n/+X/
3f/i/+D/5f/l/+X/5f/n/+f/4P/g/+D/5f/l/+L/5f/l/+X/5f/l/+L/4v/i
/+X/4v/n/+L/5f/n/+X/4P/g/+X/5f/g/+L/5f/i/+L/3f/g/93/4P/l/+X/
3f/g/+D/3f/g/+D/4P/l/+f/5f/g/+X/4v/g/9v/2//b/+L/5f/i/9v/2//d
/93/3f/b/9

#包括
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类XmlStreamLint
{
公众：
Q_DECLARE_TR_函数（XmlStreamLint）
};
int main（int argc，char*argv[]）
{
枚举出口代码
{
成功,，
如果失败，
论点错误，
作家错误，
文件失败
};
QCore应用程序应用程序（argc、argv）；
QTextStream errorStream（stderr）；
如果（argc！=2）
{
错误流
戴夫
让我重新发布代码和示例xml。我已删除错误捕获条件

QString inputFilePath(QCoreApplication::arguments().at(1));
QFile inputFile(inputFilePath);
QString outputfilepath="/home/shakeel/xmlstreamlint/testing.xml";
QFile outputFile(outputfilepath);
QByteArray array[2000];
QByteArray *ptr;
ptr=&array[0];
QXmlStreamReader reader(&inputFile);
QXmlStreamWriter writer(ptr);
QString text,signal;
while (!reader.atEnd())
{
    reader.readNext();
    } else
        if (reader.isStartElement())
        {
            text = reader.name().toString();
            if(text.operator ==("TYPICAL_CYCLE_CHANNEL"))
            {
           signal=reader.readElementtext();
            }
        }
        writer.writeCurrentToken(reader);    

}
只需添加右大括号xml就完成了
看看这是否有帮助
关于
我试图格式化您的代码（如果得到版主的批准，代码将可见），但即使如此，您的Qt代码和Xml文档都不完整。如果您能够提供更完整的代码和Xml，您可能会得到一些答案。