qt设置过滤器

1.创建事件过滤器类，在主窗口中安装事件过滤器

class PasteFilter : public QObject {Q_OBJECTpublic:PasteFilter(QObject *parent = nullptr) : QObject(parent) {}protected:bool eventFilter(QObject *obj, QEvent *event) override {if (event->type() == QEvent::KeyPress) {QKeyEvent *keyEvent = static_cast<QKeyEvent *>(event);if (keyEvent->modifiers() == Qt::ControlModifier && keyEvent->key() == Qt::Key_V) {QTextEdit *textEdit = qobject_cast<QTextEdit *>(obj);if (textEdit) {QClipboard *clipboard = QApplication::clipboard();QString clipboardText = clipboard->text();QString quotedText = "\"" + clipboardText + "\"";QTextCursor cursor = textEdit->textCursor();cursor.insertText(quotedText);return true;}}}return QObject::eventFilter(obj, event);}
};PasteFilter *pasteFilter = new PasteFilter(this);ui->textEdit->installEventFilter(pasteFilter);

2. 自定义控件，重写控件的event事件

    void keyPressEvent(QKeyEvent *event) override {if (event->modifiers() == Qt::ControlModifier && event->key() == Qt::Key_V) {// 捕获 Ctrl+V 事件QClipboard *clipboard = QApplication::clipboard();QString originalText = clipboard->text();QString quotedText = "\"" + originalText + "\"";// 插入带引号的文本this->insertPlainText(quotedText);} else {// 调用基类的方法处理其他按键事件QTextEdit::keyPressEvent(event);}}