Qt 5.11 | Qt Widgets | QRegularExpression Example | regularexpressiondialog.cpp Example File

Qt 5.11.3 Reference Documentation

# regularexpressiondialog.cpp Example File

tools/regularexpression/regularexpressiondialog.cpp

      /****************************************************************************
      **
      ** Copyright (C) 2016 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Giuseppe D'Angelo <giuseppe.dangelo@kdab.com>
      ** Copyright (C) 2016 Samuel Gaist <samuel.gaist@edeltech.ch>
      ** Copyright (C) 2016 The Qt Company Ltd.
      ** Contact: https://www.qt.io/licensing/
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      ** This file is part of the examples of the Qt Toolkit.
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      #include "regularexpressiondialog.h"

      #include <QApplication>

      #include <QCheckBox>
      #include <QComboBox>
      #include <QLabel>
      #include <QLineEdit>
      #include <QMenu>
      #include <QSpinBox>
      #include <QPlainTextEdit>
      #include <QTreeWidget>

      #include <QAction>
      #include <QClipboard>
      #include <QContextMenuEvent>

      #include <QHBoxLayout>
      #include <QGridLayout>
      #include <QFormLayout>

      #include <QRegularExpression>
      #include <QRegularExpressionMatch>
      #include <QRegularExpressionMatchIterator>

      Q_DECLARE_METATYPE(QRegularExpression::MatchType)

      static QString rawStringLiteral(QString pattern)
      {
          pattern.prepend(QLatin1String("R\"RX("));
          pattern.append(QLatin1String(")RX\""));
          return pattern;
      }

      static QString patternToCode(QString pattern)
      {
          pattern.replace(QLatin1String("\\"), QLatin1String("\\\\"));
          pattern.replace(QLatin1String("\""), QLatin1String("\\\""));
          pattern.prepend(QLatin1Char('"'));
          pattern.append(QLatin1Char('"'));
          return pattern;
      }

      static QString codeToPattern(QString code)
      {
          for (int i = 0; i < code.size(); ++i) {
              if (code.at(i) == QLatin1Char('\\'))
                  code.remove(i, 1);
          }
          if (code.startsWith(QLatin1Char('"')) && code.endsWith(QLatin1Char('"'))) {
              code.chop(1);
              code.remove(0, 1);
          }
          return code;
      }

      class PatternLineEdit : public QLineEdit
      {
          Q_OBJECT
      public:
          explicit PatternLineEdit(QWidget *parent = nullptr);

      private slots:
          void copyToCode();
          void pasteFromCode();
          void escapeSelection();

      protected:
          void contextMenuEvent(QContextMenuEvent *event) override;

      private:
          QAction *escapeSelectionAction;
          QAction *copyToCodeAction;
          QAction *pasteFromCodeAction;
      };

      PatternLineEdit::PatternLineEdit(QWidget *parent) :
          QLineEdit(parent),
          escapeSelectionAction(new QAction(tr("Escape Selection"), this)),
          copyToCodeAction(new QAction(tr("Copy to Code"), this)),
          pasteFromCodeAction(new QAction(tr("Paste from Code"), this))
      {
          setClearButtonEnabled(true);
          connect(escapeSelectionAction, &QAction::triggered, this, &PatternLineEdit::escapeSelection);
          connect(copyToCodeAction, &QAction::triggered, this, &PatternLineEdit::copyToCode);
          connect(pasteFromCodeAction, &QAction::triggered, this, &PatternLineEdit::pasteFromCode);
      #if !QT_CONFIG(clipboard)
          copyToCodeAction->setEnabled(false);
          pasteFromCodeAction->setEnabled(false);
      #endif
      }

      void PatternLineEdit::escapeSelection()
      {
          const QString selection = selectedText();
          const QString escapedSelection = QRegularExpression::escape(selection);
          if (escapedSelection != selection) {
              QString t = text();
              t.replace(selectionStart(), selection.size(), escapedSelection);
              setText(t);
          }
      }

      void PatternLineEdit::copyToCode()
      {
      #if QT_CONFIG(clipboard)
          QGuiApplication::clipboard()->setText(patternToCode(text()));
      #endif
      }

      void PatternLineEdit::pasteFromCode()
      {
      #if QT_CONFIG(clipboard)
          setText(codeToPattern(QGuiApplication::clipboard()->text()));
      #endif
      }

      void PatternLineEdit::contextMenuEvent(QContextMenuEvent *event)
      {
          QMenu *menu = createStandardContextMenu();
          menu->setAttribute(Qt::WA_DeleteOnClose);
          menu->addSeparator();
          escapeSelectionAction->setEnabled(hasSelectedText());
          menu->addAction(escapeSelectionAction);
          menu->addSeparator();
          menu->addAction(copyToCodeAction);
          menu->addAction(pasteFromCodeAction);
          menu->popup(event->globalPos());
      }

      class DisplayLineEdit : public QLineEdit
      {
      public:
          explicit DisplayLineEdit(QWidget *parent = nullptr);
      };

      DisplayLineEdit::DisplayLineEdit(QWidget *parent) : QLineEdit(parent)
      {
          setReadOnly(true);
          QPalette disabledPalette = palette();
          disabledPalette.setBrush(QPalette::Base, disabledPalette.brush(QPalette::Disabled, QPalette::Base));
          setPalette(disabledPalette);

      #if QT_CONFIG(clipboard)
          QAction *copyAction = new QAction(this);
          copyAction->setText(RegularExpressionDialog::tr("Copy to clipboard"));
          copyAction->setIcon(QIcon(QStringLiteral(":/images/copy.png")));
          connect(copyAction, &QAction::triggered, this,
                  [this] () { QGuiApplication::clipboard()->setText(text()); });
          addAction(copyAction, QLineEdit::TrailingPosition);
      #endif
      }

      RegularExpressionDialog::RegularExpressionDialog(QWidget *parent)
          : QDialog(parent)
      {
          setupUi();
          setWindowTitle(tr("QRegularExpression Example"));

          connect(patternLineEdit, &QLineEdit::textChanged, this, &RegularExpressionDialog::refresh);
          connect(subjectTextEdit, &QPlainTextEdit::textChanged, this, &RegularExpressionDialog::refresh);

          connect(caseInsensitiveOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(dotMatchesEverythingOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(multilineOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(extendedPatternSyntaxOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(invertedGreedinessOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(dontCaptureOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(useUnicodePropertiesOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(optimizeOnFirstUsageOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(dontAutomaticallyOptimizeOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);

          connect(offsetSpinBox, QOverload<int>::of(&QSpinBox::valueChanged),
                  this, &RegularExpressionDialog::refresh);

          connect(matchTypeComboBox, QOverload<int>::of(&QComboBox::currentIndexChanged),
                  this, &RegularExpressionDialog::refresh);

          connect(anchoredMatchOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);
          connect(dontCheckSubjectStringMatchOptionCheckBox, &QCheckBox::toggled, this, &RegularExpressionDialog::refresh);

          patternLineEdit->setText(tr("(\\+?\\d+)-(?<prefix>\\d+)-(?<number>\\w+)"));
          subjectTextEdit->setPlainText(tr("My office number is +43-152-0123456, my mobile is 001-41-255512 instead."));

          refresh();
      }

      void RegularExpressionDialog::setResultUiEnabled(bool enabled)
      {
          matchDetailsTreeWidget->setEnabled(enabled);
          namedGroupsTreeWidget->setEnabled(enabled);
      }

      static void setTextColor(QWidget *widget, const QColor &color)
      {
          QPalette palette = widget->palette();
          palette.setColor(QPalette::Text, color);
          widget->setPalette(palette);
      }

      void RegularExpressionDialog::refresh()
      {
          setUpdatesEnabled(false);

          const QString pattern = patternLineEdit->text();
          const QString text = subjectTextEdit->toPlainText();

          offsetSpinBox->setMaximum(qMax(0, text.length() - 1));

          escapedPatternLineEdit->setText(patternToCode(pattern));
          rawStringLiteralLineEdit->setText(rawStringLiteral(pattern));

          setTextColor(patternLineEdit, subjectTextEdit->palette().color(QPalette::Text));
          matchDetailsTreeWidget->clear();
          namedGroupsTreeWidget->clear();
          regexpStatusLabel->setText(QString());

          if (pattern.isEmpty()) {
              setResultUiEnabled(false);
              setUpdatesEnabled(true);
              return;
          }

          QRegularExpression rx(pattern);
          if (!rx.isValid()) {
              setTextColor(patternLineEdit, Qt::red);
              regexpStatusLabel->setText(tr("Invalid: syntax error at position %1 (%2)")
                                         .arg(rx.patternErrorOffset())
                                         .arg(rx.errorString()));
              setResultUiEnabled(false);
              setUpdatesEnabled(true);
              return;
          }

          setResultUiEnabled(true);

          QRegularExpression::MatchType matchType = matchTypeComboBox->currentData().value<QRegularExpression::MatchType>();
          QRegularExpression::PatternOptions patternOptions = QRegularExpression::NoPatternOption;
          QRegularExpression::MatchOptions matchOptions = QRegularExpression::NoMatchOption;

          if (anchoredMatchOptionCheckBox->isChecked())
              matchOptions |= QRegularExpression::AnchoredMatchOption;
          if (dontCheckSubjectStringMatchOptionCheckBox->isChecked())
              matchOptions |= QRegularExpression::DontCheckSubjectStringMatchOption;

          if (caseInsensitiveOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::CaseInsensitiveOption;
          if (dotMatchesEverythingOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::DotMatchesEverythingOption;
          if (multilineOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::MultilineOption;
          if (extendedPatternSyntaxOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::ExtendedPatternSyntaxOption;
          if (invertedGreedinessOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::InvertedGreedinessOption;
          if (dontCaptureOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::DontCaptureOption;
          if (useUnicodePropertiesOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::UseUnicodePropertiesOption;
          if (optimizeOnFirstUsageOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::OptimizeOnFirstUsageOption;
          if (dontAutomaticallyOptimizeOptionCheckBox->isChecked())
              patternOptions |= QRegularExpression::DontAutomaticallyOptimizeOption;

          rx.setPatternOptions(patternOptions);

          const int capturingGroupsCount = rx.captureCount() + 1;

          QRegularExpressionMatchIterator iterator = rx.globalMatch(text, offsetSpinBox->value(), matchType, matchOptions);
          int i = 0;

          while (iterator.hasNext()) {
              QRegularExpressionMatch match = iterator.next();

              QTreeWidgetItem *matchDetailTopItem = new QTreeWidgetItem(matchDetailsTreeWidget);
              matchDetailTopItem->setText(0, QString::number(i));

              for (int captureGroupIndex = 0; captureGroupIndex < capturingGroupsCount; ++captureGroupIndex) {
                  QTreeWidgetItem *matchDetailItem = new QTreeWidgetItem(matchDetailTopItem);
                  matchDetailItem->setText(1, QString::number(captureGroupIndex));
                  matchDetailItem->setText(2, match.captured(captureGroupIndex));
              }

              ++i;
          }

          matchDetailsTreeWidget->expandAll();

          regexpStatusLabel->setText(tr("Valid"));

          const QStringList namedCaptureGroups = rx.namedCaptureGroups();
          for (int i = 0; i < namedCaptureGroups.size(); ++i) {
              const QString currentNamedCaptureGroup = namedCaptureGroups.at(i);

              QTreeWidgetItem *namedGroupItem = new QTreeWidgetItem(namedGroupsTreeWidget);
              namedGroupItem->setText(0, QString::number(i));
              namedGroupItem->setText(1, currentNamedCaptureGroup.isNull() ? tr("<no name>") : currentNamedCaptureGroup);
          }

          setUpdatesEnabled(true);
      }

      void RegularExpressionDialog::setupUi()
      {
          QWidget *leftHalfContainer = setupLeftUi();

          QFrame *verticalSeparator = new QFrame;
          verticalSeparator->setFrameStyle(QFrame::VLine | QFrame::Sunken);

          QWidget *rightHalfContainer = setupRightUi();

          QHBoxLayout *mainLayout = new QHBoxLayout;
          mainLayout->addWidget(leftHalfContainer);
          mainLayout->addWidget(verticalSeparator);
          mainLayout->addWidget(rightHalfContainer);

          setLayout(mainLayout);
      }

      QWidget *RegularExpressionDialog::setupLeftUi()
      {
          QWidget *container = new QWidget;

          QFormLayout *layout = new QFormLayout(container);
          layout->setFieldGrowthPolicy(QFormLayout::AllNonFixedFieldsGrow);
          layout->setMargin(0);

          QLabel *regexpAndSubjectLabel = new QLabel(tr("<h3>Regular expression and text input</h3>"));
          layout->addRow(regexpAndSubjectLabel);

          patternLineEdit = new PatternLineEdit;
          patternLineEdit->setClearButtonEnabled(true);
          layout->addRow(tr("&Pattern:"), patternLineEdit);

          rawStringLiteralLineEdit = new DisplayLineEdit;
          layout->addRow(tr("&Raw string literal:"), rawStringLiteralLineEdit);
          escapedPatternLineEdit = new DisplayLineEdit;
          layout->addRow(tr("&Escaped pattern:"), escapedPatternLineEdit);

          subjectTextEdit = new QPlainTextEdit;
          layout->addRow(tr("&Subject text:"), subjectTextEdit);

          caseInsensitiveOptionCheckBox = new QCheckBox(tr("Case insensitive (/i)"));
          dotMatchesEverythingOptionCheckBox = new QCheckBox(tr("Dot matches everything (/s)"));
          multilineOptionCheckBox = new QCheckBox(tr("Multiline (/m)"));
          extendedPatternSyntaxOptionCheckBox = new QCheckBox(tr("Extended pattern (/x)"));
          invertedGreedinessOptionCheckBox = new QCheckBox(tr("Inverted greediness"));
          dontCaptureOptionCheckBox = new QCheckBox(tr("Don't capture"));
          useUnicodePropertiesOptionCheckBox = new QCheckBox(tr("Use unicode properties (/u)"));
          optimizeOnFirstUsageOptionCheckBox = new QCheckBox(tr("Optimize on first usage"));
          dontAutomaticallyOptimizeOptionCheckBox = new QCheckBox(tr("Don't automatically optimize"));

          QGridLayout *patternOptionsCheckBoxLayout = new QGridLayout;
          int gridRow = 0;
          patternOptionsCheckBoxLayout->addWidget(caseInsensitiveOptionCheckBox, gridRow, 1);
          patternOptionsCheckBoxLayout->addWidget(dotMatchesEverythingOptionCheckBox, gridRow, 2);
          ++gridRow;
          patternOptionsCheckBoxLayout->addWidget(multilineOptionCheckBox, gridRow, 1);
          patternOptionsCheckBoxLayout->addWidget(extendedPatternSyntaxOptionCheckBox, gridRow, 2);
          ++gridRow;
          patternOptionsCheckBoxLayout->addWidget(invertedGreedinessOptionCheckBox, gridRow, 1);
          patternOptionsCheckBoxLayout->addWidget(dontCaptureOptionCheckBox, gridRow, 2);
          ++gridRow;
          patternOptionsCheckBoxLayout->addWidget(useUnicodePropertiesOptionCheckBox, gridRow, 1);
          patternOptionsCheckBoxLayout->addWidget(optimizeOnFirstUsageOptionCheckBox, gridRow, 2);
          ++gridRow;
          patternOptionsCheckBoxLayout->addWidget(dontAutomaticallyOptimizeOptionCheckBox, gridRow, 1);

          layout->addRow(tr("Pattern options:"), patternOptionsCheckBoxLayout);

          offsetSpinBox = new QSpinBox;
          layout->addRow(tr("Match &offset:"), offsetSpinBox);

          matchTypeComboBox = new QComboBox;
          matchTypeComboBox->addItem(tr("Normal"), QVariant::fromValue(QRegularExpression::NormalMatch));
          matchTypeComboBox->addItem(tr("Partial prefer complete"), QVariant::fromValue(QRegularExpression::PartialPreferCompleteMatch));
          matchTypeComboBox->addItem(tr("Partial prefer first"), QVariant::fromValue(QRegularExpression::PartialPreferFirstMatch));
          matchTypeComboBox->addItem(tr("No match"), QVariant::fromValue(QRegularExpression::NoMatch));
          layout->addRow(tr("Match &type:"), matchTypeComboBox);

          dontCheckSubjectStringMatchOptionCheckBox = new QCheckBox(tr("Don't check subject string"));
          anchoredMatchOptionCheckBox = new QCheckBox(tr("Anchored match"));

          QGridLayout *matchOptionsCheckBoxLayout = new QGridLayout;
          matchOptionsCheckBoxLayout->addWidget(dontCheckSubjectStringMatchOptionCheckBox, 0, 0);
          matchOptionsCheckBoxLayout->addWidget(anchoredMatchOptionCheckBox, 0, 1);
          layout->addRow(tr("Match options:"), matchOptionsCheckBoxLayout);

          return container;
      }

      QWidget *RegularExpressionDialog::setupRightUi()
      {
          QWidget *container = new QWidget;

          QFormLayout *layout = new QFormLayout(container);
          layout->setFieldGrowthPolicy(QFormLayout::AllNonFixedFieldsGrow);
          layout->setMargin(0);

          QLabel *matchInfoLabel = new QLabel(tr("<h3>Match information</h3>"));
          layout->addRow(matchInfoLabel);

          matchDetailsTreeWidget = new QTreeWidget;
          matchDetailsTreeWidget->setHeaderLabels(QStringList() << tr("Match index") << tr("Group index") << tr("Captured string"));
          matchDetailsTreeWidget->setSizeAdjustPolicy(QTreeWidget::AdjustToContents);
          layout->addRow(tr("Match details:"), matchDetailsTreeWidget);

          QFrame *horizontalSeparator = new QFrame;
          horizontalSeparator->setFrameStyle(QFrame::HLine | QFrame::Sunken);
          layout->addRow(horizontalSeparator);

          QLabel *regexpInfoLabel = new QLabel(tr("<h3>Regular expression information</h3>"));
          layout->addRow(regexpInfoLabel);

          regexpStatusLabel = new QLabel(tr("Valid"));
          regexpStatusLabel->setWordWrap(true);
          layout->addRow(tr("Pattern status:"), regexpStatusLabel);

          namedGroupsTreeWidget = new QTreeWidget;
          namedGroupsTreeWidget->setHeaderLabels(QStringList() << tr("Index") << tr("Named group"));
          namedGroupsTreeWidget->setSizeAdjustPolicy(QTreeWidget::AdjustToContents);
          namedGroupsTreeWidget->setRootIsDecorated(false);
          layout->addRow(tr("Named groups:"), namedGroupsTreeWidget);

          return container;
      }

      #include "regularexpressiondialog.moc"