Qt--命令行终端程序开发

提示：本文为学习记录，若有错误，请联系作者，谦虚受教。

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前言

Constant dropping wears the stone.

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一、头文件

#ifndef TERMINALWIDGET_H
#define TERMINALWIDGET_H#include <QTextEdit>
#include <QKeyEvent>
#include <QFont>
#include <QProcess>
#include <QByteArray>
#include <QLabel>
#include <QHBoxLayout>
#include <QVBoxLayout>
#include <QTextLayout>
#include <QTextCursor>
#include <QTextBlock>
#include <QTextCodec>
#include <assert.h>class TerminalWidget: public QTextEdit
{Q_OBJECT
public:TerminalWidget();protected:void keyPressEvent(QKeyEvent *e);private:// 字体QFont font;// 命令行终端进程QProcess * proc;// 光标位置long long lastPosition = 0;// 上一次的输入内容QByteArray lastInput;public slots:/*** @brief readyReadStandardOutputSlot       标准输出*/void readyReadStandardOutputSlot();/*** @brief readyReadStandardErrorSlot        错误输出*/void readyReadStandardErrorSlot();
};#endif // TERMINALWIDGET_H

二、cpp文件

#include "terminalwidget.h"
#include <QDebug>TerminalWidget::TerminalWidget()
{setStyleSheet("background-color:rgb(0,0,0); color:rgb(255,255,255); border:0px;");setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);resize(1000,700);setWindowTitle("命令行提示符");font.setFamily("Times New Roman");font.setPixelSize(14);setFont(font);proc = new QProcess();connect(proc,SIGNAL(readyReadStandardOutput()),this,SLOT(readyReadStandardOutputSlot()));connect(proc,SIGNAL(readyReadStandardError()),this,SLOT(readyReadStandardErrorSlot()));#ifdef Q_OS_WINproc->start("cmd");
#elif Q_OS_LINUXproc->start("bash");
#endifQTextCursor editCursor = textCursor();QTextBlockFormat textBlockFormat;textBlockFormat.setLineHeight(20, QTextBlockFormat::FixedHeight);editCursor.setBlockFormat(textBlockFormat);setTextCursor(editCursor);
}void TerminalWidget::keyPressEvent(QKeyEvent *e)
{QTextCursor editCursor = textCursor();// Qt::Key_Enter 是小键盘（数字键盘）的 Enter，对应的虚拟键码为：0x01000005// Qt::Key_Return 是大键盘区的 Enter，对应的虚拟键码为：0x01000004if(e->key() == Qt::Key_Return || e->key() == Qt::Key_Enter){e->ignore();editCursor.setPosition(lastPosition, QTextCursor::MoveAnchor);editCursor.movePosition(QTextCursor::End, QTextCursor::KeepAnchor);QString string = editCursor.selectedText();editCursor.clearSelection();
#ifdef Q_OS_WINlastInput =  string.toLocal8Bit() + '\r' + '\n';
#elif Q_OS_LINUXlastInput =  string.toLocal8Bit() + '\n';
#endifproc->write(lastInput);return;}else if(e->key() == Qt::Key_Backspace && editCursor.position() <= lastPosition)return;else if(e->key() == Qt::Key_Delete && editCursor.position() <= lastPosition)return;elsereturn QTextEdit::keyPressEvent(e);
}void TerminalWidget::readyReadStandardOutputSlot()
{QByteArray ba = proc->readAllStandardOutput();QTextCodec * textCodec = QTextCodec::codecForName("System");// assert 断言，如果 textCodec 为空，则编译报错assert(textCodec != nullptr);QString output = textCodec->toUnicode(ba);if (output.length() > 0 && output != QString::fromLocal8Bit(lastInput)){setTextColor(Qt::white);append(output.trimmed());moveCursor(QTextCursor::End);lastPosition = textCursor().position();}
}void TerminalWidget::readyReadStandardErrorSlot()
{QByteArray ba = proc->readAllStandardError();QTextCodec* textCodec = QTextCodec::codecForName("System");// assert 断言，如果 textCodec 为空，则编译报错assert(textCodec != nullptr);QString output = textCodec->toUnicode(ba);if (output.length() > 0 && output != QString::fromLocal8Bit(lastInput)){setTextColor(Qt::red);append(output.trimmed());moveCursor(QTextCursor::End);lastPosition = textCursor().position();}
}

三、使用流程

主要使用process来命令行操作

代码如下（示例）：

int main(int argc,char *argv[])
{
QAPPlication a(argc,argv);
TerminalWidget w;
w.show();
return a,exec();
}

如图所示

总结

善于总结，多进一步。