《QT5.9 c++ 开发指南》第7章 二进制文件读写

       本章有3个自定义组件的，这里就不详细去细讲，后期会有一章全面的讲解，由于时间问题，例子里面中文是对每个代码的解析，希望简单去记录里面的实现过程：

老规矩，先上页面布局，后期需要源码的同学们，留言我会添加进取：

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include    <QMainWindow>
#include    <QLabel>
#include    <QStandardItemModel>
#include    <QItemSelectionModel>

#include    "qwintspindelegate.h"
#include    "qwfloatspindelegate.h"
#include    "qwcomboboxdelegate.h"


#define     FixedColumnCount    6       //文件固定6行

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT
private:

//用于状态栏的信息显示
//    QLabel  *LabCurFile;  //当前文件
    QLabel  *LabCellPos;    //当前单元格行列号
    QLabel  *LabCellText;   //当前单元格内容

    QWIntSpinDelegate    intSpinDelegate; //整型数
    QWFloatSpinDelegate  floatSpinDelegate; //浮点数
    QWComboBoxDelegate   comboBoxDelegate; //列表选择

//    QString fCurFile;//当前文件名

    QStandardItemModel  *theModel;//数据模型
    QItemSelectionModel *theSelection;//Item选择模型

//    void    iniModelFromStringList(QStringList&);//从StringList初始化数据模型

    void    resetTable(int aRowCount);  //表格复位，设定行数
    bool    saveDataAsStream(QString& aFileName);//将数据保存为数据流文件
    bool    openDataAsStream(QString& aFileName);//读取数据流文件

    bool    saveBinaryFile(QString& aFileName);//保存为二进制文件
    bool    openBinaryFile(QString& aFileName);//打开二进制文件

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private slots:
    void on_currentChanged(const QModelIndex &current, const QModelIndex &previous);

    void on_actOpen_triggered(); //打开文件

    void on_actAppend_triggered(); //添加行

    void on_actInsert_triggered();//插入行

    void on_actDelete_triggered();//删除行

    void on_actSave_triggered();//保存文件

    void on_actAlignCenter_triggered(); //居中对齐

    void on_actFontBold_triggered(bool checked); //字体粗体设置

    void on_actAlignLeft_triggered(); //左对齐

    void on_actAlignRight_triggered(); //右对齐

    void on_actTabReset_triggered(); //表格复位

    void on_actSaveBin_triggered(); //保存为自编码二进制文件

    void on_actOpenBin_triggered(); //打开自编码二进制文件

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include    <QFileDialog>
#include    <QDataStream>
#include    <QMessageBox>
//#include    "qw.h"

void MainWindow::resetTable(int aRowCount)
{ //表格复位，先删除所有行，再设置新的行数，表头不变
//    QStringList     headerList;
//    headerList<<"测深(m)"<<"垂深(m)"<<"方位(°)"<<"总位移(m)"<<"固井质量"<<"测井取样";
//    theModel->setHorizontalHeaderLabels(headerList); //设置表头文字

    theModel->removeRows(0,theModel->rowCount()); //删除所有行
    theModel->setRowCount(aRowCount);//设置新的行数

//    QStandardItem   *aItem;
//    QModelIndex     index;
    QString str=theModel->headerData(theModel->columnCount()-1,
                     Qt::Horizontal,Qt::DisplayRole).toString();

    for (int i=0;i<theModel->rowCount();i++)
    { //设置最后一列
        QModelIndex index=theModel->index(i,FixedColumnCount-1); //获取模型索引
        QStandardItem* aItem=theModel->itemFromIndex(index); //获取item
        aItem->setCheckable(true);
        aItem->setData(str,Qt::DisplayRole);
        aItem->setEditable(false); //不可编辑
    }
}

bool MainWindow::saveDataAsStream(QString &aFileName)
{//将模型数据保存为Qt预定义编码的数据文件
    QFile aFile(aFileName);  //以文件方式读出
    if (!(aFile.open(QIODevice::WriteOnly | QIODevice::Truncate)))
        return false;

    QDataStream aStream(&aFile);
    aStream.setVersion(QDataStream::Qt_5_9); //设置版本号，写入和读取的版本号要兼容

    qint16  rowCount=theModel->rowCount(); //数据模型行数
    qint16  colCount=theModel->columnCount(); //数据模型列数

    aStream<<rowCount; //写入文件流，行数
    aStream<<colCount;//写入文件流，列数

//获取表头文字
    for (int i=0;i<theModel->columnCount();i++)
    {
        QString str=theModel->horizontalHeaderItem(i)->text();//获取表头文字
        aStream<<str; //字符串写入文件流，Qt预定义编码方式
    }


//获取数据区的数据
//    qint16  ceShen;
//    qreal  chuiShen;
//    qreal  fangWei;
//    qreal  weiYi;
//    QString  zhiLiang;
//    bool    quYang;
//    QStandardItem   *aItem;
    for (int i=0;i<theModel->rowCount();i++)
    {
        QStandardItem* aItem=theModel->item(i,0); //测深
        qint16 ceShen=aItem->data(Qt::DisplayRole).toInt();
        aStream<<ceShen;// 写入文件流，qint16

        aItem=theModel->item(i,1); //垂深
        qreal chuiShen=aItem->data(Qt::DisplayRole).toFloat();
        aStream<<chuiShen;//写入文件流， qreal

        aItem=theModel->item(i,2); //方位
        qreal fangWei=aItem->data(Qt::DisplayRole).toFloat();
        aStream<<fangWei;//写入文件流， qreal

        aItem=theModel->item(i,3); //位移
        qreal weiYi=aItem->data(Qt::DisplayRole).toFloat();
        aStream<<weiYi;//写入文件流， qreal

        aItem=theModel->item(i,4); //固井质量
        QString zhiLiang=aItem->data(Qt::DisplayRole).toString();
        aStream<<zhiLiang;// 写入文件流，字符串

        aItem=theModel->item(i,5); //测井
        bool quYang=(aItem->checkState()==Qt::Checked);
        aStream<<quYang;// 写入文件流，bool型
    }
    aFile.close();
    return true;
}

bool MainWindow::openDataAsStream(QString &aFileName)
{ //从Qt预定义流文件读入数据
    QFile aFile(aFileName);  //以文件方式读出
    if (!(aFile.open(QIODevice::ReadOnly)))
        return false;

    QDataStream aStream(&aFile); //用文本流读取文件
    aStream.setVersion(QDataStream::Qt_5_9); //设置流文件版本号

    qint16  rowCount,colCount;
    aStream>>rowCount; //读取行数
    aStream>>colCount; //列数

    this->resetTable(rowCount); //表格复位

    //获取表头文字
    QString str;
    for (int i=0;i<colCount;i++)
        aStream>>str;  //读取表头字符串

    //获取数据区文字，
    qint16  ceShen;
    qreal  chuiShen;
    qreal  fangWei;
    qreal  weiYi;
    QString  zhiLiang;
    bool    quYang;
    QStandardItem   *aItem;
    QModelIndex index;

    for (int i=0;i<rowCount;i++)
    {
        aStream>>ceShen;//读取测深, qint16
        index=theModel->index(i,0);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(ceShen,Qt::DisplayRole);

        aStream>>chuiShen;//垂深,qreal
        index=theModel->index(i,1);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(chuiShen,Qt::DisplayRole);


        aStream>>fangWei;//方位,qreal
        index=theModel->index(i,2);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(fangWei,Qt::DisplayRole);


        aStream>>weiYi;//位移,qreal
        index=theModel->index(i,3);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(weiYi,Qt::DisplayRole);


        aStream>>zhiLiang;//固井质量,QString
        index=theModel->index(i,4);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(zhiLiang,Qt::DisplayRole);

        aStream>>quYang;//bool
        index=theModel->index(i,5);
        aItem=theModel->itemFromIndex(index);
        if (quYang)
            aItem->setCheckState(Qt::Checked);
        else
            aItem->setCheckState(Qt::Unchecked);
    }

    aFile.close();
    return true;
}

bool MainWindow::saveBinaryFile(QString &aFileName)
{ //保存为纯二进制文件
    QFile aFile(aFileName);  //以文件方式读出
    if (!(aFile.open(QIODevice::WriteOnly)))
        return false;

    QDataStream aStream(&aFile); //用文本流读取文件
//    aStream.setVersion(QDataStream::Qt_5_9); //无需设置数据流的版本
    aStream.setByteOrder(QDataStream::LittleEndian);//windows平台
//    aStream.setByteOrder(QDataStream::BigEndian);//QDataStream::LittleEndian

    qint16  rowCount=theModel->rowCount();
    qint16  colCount=theModel->columnCount();

    aStream.writeRawData((char *)&rowCount,sizeof(qint16)); //写入文件流
    aStream.writeRawData((char *)&colCount,sizeof(qint16));//写入文件流


//获取表头文字
//    QString str;
    QByteArray  btArray;
    QStandardItem   *aItem;
    for (int i=0;i<theModel->columnCount();i++)
    {
        aItem=theModel->horizontalHeaderItem(i); //获取表头item
        QString str=aItem->text(); //获取表头文字
        btArray=str.toUtf8(); //转换为字符数组
        aStream.writeBytes(btArray,btArray.length()); //写入文件流,长度uint型，然后是字符串内容
    }

//获取数据区文字，
//    qint16  ceShen;
//    qreal  chuiShen;
//    qreal  fangWei;
//    qreal  weiYi;
//    QString  zhiLiang;
//    bool    quYang;
    qint8   yes=1,no=0; //分别代表逻辑值 true和false
    for (int i=0;i<theModel->rowCount();i++)
    {
        aItem=theModel->item(i,0); //测深
        qint16 ceShen=aItem->data(Qt::DisplayRole).toInt();//qint16类型
        aStream.writeRawData((char *)&ceShen,sizeof(qint16));//写入文件流

        aItem=theModel->item(i,1); //垂深
        qreal chuiShen=aItem->data(Qt::DisplayRole).toFloat();//qreal 类型
        aStream.writeRawData((char *)&chuiShen,sizeof(qreal));//写入文件流

        aItem=theModel->item(i,2); //方位
        qreal fangWei=aItem->data(Qt::DisplayRole).toFloat();
        aStream.writeRawData((char *)&fangWei,sizeof(qreal));

        aItem=theModel->item(i,3); //位移
        qreal weiYi=aItem->data(Qt::DisplayRole).toFloat();
        aStream.writeRawData((char *)&weiYi,sizeof(qreal));

        aItem=theModel->item(i,4); //固井质量
        QString zhiLiang=aItem->data(Qt::DisplayRole).toString();
        btArray=zhiLiang.toUtf8();
        aStream.writeBytes(btArray,btArray.length()); //写入长度,uint，然后是字符串
//        aStream.writeRawData(btArray,btArray.length());//对于字符串，应使用writeBytes()函数

        aItem=theModel->item(i,5); //测井取样
        bool quYang=(aItem->checkState()==Qt::Checked); //true or false
        if (quYang)
            aStream.writeRawData((char *)&yes,sizeof(qint8));
        else
            aStream.writeRawData((char *)&no,sizeof(qint8));
    }

    aFile.close();
    return true;
}

bool MainWindow::openBinaryFile(QString &aFileName)
{//打开二进制文件
    QFile aFile(aFileName);  //以文件方式读出
    if (!(aFile.open(QIODevice::ReadOnly)))
        return false;

    QDataStream aStream(&aFile); //用文本流读取文件
//    aStream.setVersion(QDataStream::Qt_5_9); //设置数据流的版本
    aStream.setByteOrder(QDataStream::LittleEndian);
//    aStream.setByteOrder(QDataStream::BigEndian);

    qint16  rowCount,colCount;
    aStream.readRawData((char *)&rowCount, sizeof(qint16));
    aStream.readRawData((char *)&colCount, sizeof(qint16));

    this->resetTable(rowCount);


    //获取表头文字,但是并不利用
//    QByteArray  btArray;
    char *buf;
    uint strLen;  //也就是 quint32
//    QString str;
    for (int i=0;i<colCount;i++)
    {
        aStream.readBytes(buf,strLen);//同时读取字符串长度，和字符串内容
        QString str=QString::fromLocal8Bit(buf,strLen); //可处理汉字
//        btArray.setRawData(buf,strLen);
//        str=QString::fromLatin1(btArray);
    }

//获取数据区数据
    QStandardItem   *aItem;

    qint16  ceShen;
    qreal  chuiShen;
    qreal  fangWei;
    qreal  weiYi;
    QString  zhiLiang;
    qint8   quYang; //分别代表逻辑值 true和false
    QModelIndex index;

    for (int i=0;i<rowCount;i++)
    {
        aStream.readRawData((char *)&ceShen, sizeof(qint16)); //测深
        index=theModel->index(i,0);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(ceShen,Qt::DisplayRole);

        aStream.readRawData((char *)&chuiShen, sizeof(qreal)); //垂深
        index=theModel->index(i,1);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(chuiShen,Qt::DisplayRole);

        aStream.readRawData((char *)&fangWei, sizeof(qreal)); //方位
        index=theModel->index(i,2);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(fangWei,Qt::DisplayRole);

        aStream.readRawData((char *)&weiYi, sizeof(qreal)); //位移
        index=theModel->index(i,3);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(weiYi,Qt::DisplayRole);

        aStream.readBytes(buf,strLen);//固井质量
        zhiLiang=QString::fromLocal8Bit(buf,strLen);
//        btArray.setRawData(buf,strLen);
//        zhiLiang=QString::fromLatin1(btArray);
        index=theModel->index(i,4);
        aItem=theModel->itemFromIndex(index);
        aItem->setData(zhiLiang,Qt::DisplayRole);

        aStream.readRawData((char *)&quYang, sizeof(qint8)); //测井取样
        index=theModel->index(i,5);
        aItem=theModel->itemFromIndex(index);
        if (quYang==1)
            aItem->setCheckState(Qt::Checked);
        else
            aItem->setCheckState(Qt::Unchecked);
    }

    aFile.close();
    return true;
}


MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    theModel = new QStandardItemModel(5,FixedColumnCount,this); //创建数据模型
    QStringList     headerList;
    headerList<<"Depth"<<"Measured Depth"<<"Direction"<<"Offset"<<"Quality"<<"Sampled";
    theModel->setHorizontalHeaderLabels(headerList); //设置表头文字


    theSelection = new QItemSelectionModel(theModel);//Item选择模型
    connect(theSelection,SIGNAL(currentChanged(QModelIndex,QModelIndex)),
            this,SLOT(on_currentChanged(QModelIndex,QModelIndex)));

    //为tableView设置数据模型
    ui->tableView->setModel(theModel); //设置数据模型
    ui->tableView->setSelectionModel(theSelection);//设置选择模型

//为各列设置自定义代理组件
    ui->tableView->setItemDelegateForColumn(0,&intSpinDelegate);  //测深，整数
    ui->tableView->setItemDelegateForColumn(1,&floatSpinDelegate);  //浮点数
    ui->tableView->setItemDelegateForColumn(2,&floatSpinDelegate); //浮点数
    ui->tableView->setItemDelegateForColumn(3,&floatSpinDelegate); //浮点数
    ui->tableView->setItemDelegateForColumn(4,&comboBoxDelegate); //Combbox选择型


    resetTable(5); //表格复位

    setCentralWidget(ui->tabWidget); //

//创建状态栏组件
//    LabCurFile = new QLabel("当前文件：",this);
//    LabCurFile->setMinimumWidth(300);

    LabCellPos = new QLabel("当前单元格：",this);
    LabCellPos->setMinimumWidth(180);
    LabCellPos->setAlignment(Qt::AlignHCenter);

    LabCellText = new QLabel("单元格内容：",this);
    LabCellText->setMinimumWidth(200);

//    ui->statusBar->addWidget(LabCurFile);
    ui->statusBar->addWidget(LabCellPos);
    ui->statusBar->addWidget(LabCellText);
//    ui->statusBar->addWidget(LabSelectionRange);
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::on_currentChanged(const QModelIndex &current, const QModelIndex &previous)
{
    if (current.isValid())
    {
        LabCellPos->setText(QString::asprintf("当前单元格：%d行，%d列",
                                  current.row(),current.column()));
        QStandardItem   *aItem;
        aItem=theModel->itemFromIndex(current); //从模型索引获得Item
        this->LabCellText->setText("单元格内容："+aItem->text());

        QFont   font=aItem->font();
        ui->actFontBold->setChecked(font.bold());
    }
}

void MainWindow::on_actOpen_triggered()
{
    QString curPath=QDir::currentPath();
//调用打开文件对话框打开一个文件
    QString aFileName=QFileDialog::getOpenFileName(this,tr("打开一个文件"),curPath,
                 "流数据文件(*.stm)");

    if (aFileName.isEmpty())
        return; //

    if  (openDataAsStream(aFileName)) //保存为流数据文件
         QMessageBox::information(this,"提示消息","文件已经打开!");
}

void MainWindow::on_actAppend_triggered()
{ //添加行
    QList<QStandardItem*>    aItemList; //容器类
    QStandardItem   *aItem;
    QString str;
    for(int i=0;i<FixedColumnCount-2;i++)
    {
        aItem=new QStandardItem("0"); //创建Item
        aItemList<<aItem;   //添加到容器
    }
    aItem=new QStandardItem("优"); //创建Item
    aItemList<<aItem;   //添加到容器

    str=theModel->headerData(theModel->columnCount()-1,Qt::Horizontal,Qt::DisplayRole).toString();
    aItem=new QStandardItem(str); //创建Item
    aItem->setCheckable(true);
    aItem->setEditable(false);
    aItemList<<aItem;   //添加到容器

    theModel->insertRow(theModel->rowCount(),aItemList); //插入一行，需要每个Cell的Item
    QModelIndex curIndex=theModel->index(theModel->rowCount()-1,0);//创建最后一行的ModelIndex
    theSelection->clearSelection();
    theSelection->setCurrentIndex(curIndex,QItemSelectionModel::Select);
}

void MainWindow::on_actInsert_triggered()
{//插入行
    QList<QStandardItem*>    aItemList;  //QStandardItem的容器类
    QStandardItem   *aItem;
    QString str;
    for(int i=0;i<FixedColumnCount-2;i++)
    {
        aItem=new QStandardItem("0"); //新建一个QStandardItem
        aItemList<<aItem;//添加到容器类
    }
    aItem=new QStandardItem("优"); //新建一个QStandardItem
    aItemList<<aItem;//添加到容器类

    str=theModel->headerData(theModel->columnCount()-1,Qt::Horizontal,Qt::DisplayRole).toString();
    aItem=new QStandardItem(str); //创建Item
    aItem->setCheckable(true);
    aItem->setEditable(false);
    aItemList<<aItem;//添加到容器类
//    theModel->insertRow(ui->tableView->currentIndex().row(),aItemList);
    QModelIndex curIndex=theSelection->currentIndex();
    theModel->insertRow(curIndex.row(),aItemList);
    theSelection->clearSelection();
    theSelection->setCurrentIndex(curIndex,QItemSelectionModel::Select);
}

void MainWindow::on_actDelete_triggered()
{ //删除行
    QModelIndex curIndex=theSelection->currentIndex();
    if (curIndex.row()==theModel->rowCount()-1)//(curIndex.isValid())
        theModel->removeRow(curIndex.row());
    else
    {
        theModel->removeRow(curIndex.row());
        theSelection->setCurrentIndex(curIndex,QItemSelectionModel::Select);
    }
}


void MainWindow::on_actSave_triggered()
{ //以Qt预定义编码保存数据文件
    QString curPath=QDir::currentPath();
    QString aFileName=QFileDialog::getSaveFileName(this,tr("选择保存文件"),curPath,
                 "Qt预定义编码数据文件(*.stm)");

    if (aFileName.isEmpty())
        return; //

   if  (saveDataAsStream(aFileName)) //保存为流数据文件
       QMessageBox::information(this,"提示消息","文件已经成功保存!");
}

void MainWindow::on_actAlignCenter_triggered()
{
    if (!theSelection->hasSelection())
        return;

    QModelIndexList selectedIndix=theSelection->selectedIndexes();

    QModelIndex aIndex;
    QStandardItem   *aItem;

    for (int i=0;i<selectedIndix.count();i++)
    {
        aIndex=selectedIndix.at(i);
        aItem=theModel->itemFromIndex(aIndex);
        aItem->setTextAlignment(Qt::AlignHCenter);
    }
}

void MainWindow::on_actFontBold_triggered(bool checked)
{
    if (!theSelection->hasSelection())
        return;

    QModelIndexList selectedIndix=theSelection->selectedIndexes();

    QModelIndex aIndex;
    QStandardItem   *aItem;
    QFont   font;

    for (int i=0;i<selectedIndix.count();i++)
    {
        aIndex=selectedIndix.at(i);
        aItem=theModel->itemFromIndex(aIndex);
        font=aItem->font();
        font.setBold(checked);
        aItem->setFont(font);
    }

}

void MainWindow::on_actAlignLeft_triggered()
{
    if (!theSelection->hasSelection())
        return;

    QModelIndexList selectedIndix=theSelection->selectedIndexes();

    QModelIndex aIndex;
    QStandardItem   *aItem;

    for (int i=0;i<selectedIndix.count();i++)
    {
        aIndex=selectedIndix.at(i);
        aItem=theModel->itemFromIndex(aIndex);
        aItem->setTextAlignment(Qt::AlignLeft);
    }
}

void MainWindow::on_actAlignRight_triggered()
{
    if (!theSelection->hasSelection())
        return;

    QModelIndexList selectedIndix=theSelection->selectedIndexes();

    QModelIndex aIndex;
    QStandardItem   *aItem;

    for (int i=0;i<selectedIndix.count();i++)
    {
        aIndex=selectedIndix.at(i);
        aItem=theModel->itemFromIndex(aIndex);
        aItem->setTextAlignment(Qt::AlignRight);
    }
}

void MainWindow::on_actTabReset_triggered()
{//表格复位
    resetTable(10);
}

void MainWindow::on_actSaveBin_triggered()
{//保存二进制文件
    QString curPath=QDir::currentPath();
    //调用打开文件对话框选择一个文件
    QString aFileName=QFileDialog::getSaveFileName(this,tr("选择保存文件"),curPath,
                                                   "二进制数据文件(*.dat)");
    if (aFileName.isEmpty())
        return; //

    if  (saveBinaryFile(aFileName)) //保存为流数据文件
        QMessageBox::information(this,"提示消息","文件已经成功保存!");
}

void MainWindow::on_actOpenBin_triggered()
{//打开二进制文件
    QString curPath=QDir::currentPath();//系统当前目录
    QString aFileName=QFileDialog::getOpenFileName(this,tr("打开一个文件"),curPath,
                                                   "二进制数据文件(*.dat)");
    if (aFileName.isEmpty())
        return; //

    if  (openBinaryFile(aFileName)) //保存为流数据文件
        QMessageBox::information(this,"提示消息","文件已经打开!");
}

对于剩下的3个头文件，我会上传项目上，需要的请留言。