Qt5：一个文本框输入字符，另一个文本框输出其大写格式

效果如下：

widget.h

#ifndef WIDGET_H

#define WIDGET_H

#include <QWidget>

#include <QLineEdit>

class Widget : public QWidget

{

    Q_OBJECT

public:

    Widget(QWidget *parent = 0);

    ~Widget();

protected slots:

    void daxie();

private:

    QLineEdit *textEdit,*textEdit2;

};

#endif // WIDGET_H

widget.cpp

#include <QWidget>

#include <QLineEdit>

#include <QApplication>

#include <QVBoxLayout>

#include "widget.h"

Widget::Widget(QWidget *parent)

    : QWidget(parent)

{

    QVBoxLayout *windowLayout = new QVBoxLayout(this);

    textEdit = new QLineEdit;

    textEdit->setEnabled(true);

    textEdit2 = new QLineEdit;

    textEdit2->setEnabled(false);

    windowLayout->addWidget(textEdit);

    windowLayout->addWidget(textEdit2);

    QObject:: connect(textEdit,SIGNAL(textChanged(QString)),this,SLOT(daxie()));

}

Widget::~Widget()

{

}

void Widget::daxie()

{

    QString newString = textEdit->text();

    textEdit2->setText(newString.toUpper());

}

main.cpp

#include "widget.h"
#include <QApplication>
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();
    return a.exec();
}