QT 实现 读取 增加 删除 实时操作xml

Posted 2021-01-23 linxuemufeng

include "operatexml.h"

include

OperateXml::OperateXml(QWidget *parent)
: QMainWindow(parent)
{
ui.setupUi(this);
readXML();
load();
connect(ui.pushButton_add, &QPushButton::clicked, this, &OperateXml::add);
connect(ui.pushButton_del, &QPushButton::clicked, this, &OperateXml::del);
connect(ui.tableView, SIGNAL(clicked(const QModelIndex &)), this,
SLOT(selectItem(const QModelIndex &)));
}

OperateXml::~OperateXml()
{

}
void OperateXml::selectItem(const QModelIndex &)
{

}
void OperateXml::add()
{
cityInfo city;
city.name = ui.lineEdit_name->text();
bool* lonOK = new bool;
bool* latOK=new bool;
QString lon = ui.lineEdit_lon->text();
city.lon = lon.toDouble(lonOK);
QString lat = ui.lineEdit_lon->text();
city.lat = lat.toDouble(latOK);
if (city.name.length() > 15)
{
QMessageBox::information(nullptr, QString::fromLocal8Bit("提示"), QString::fromLocal8Bit("名称长度超过15个字符")); return;
}
if (city.name.trimmed().length() ==0)
{
QMessageBox::information(nullptr, QString::fromLocal8Bit("提示"), QString::fromLocal8Bit("名称不能为空")); return;
}
if (lonOK == false)
{
QMessageBox::information(nullptr, QString::fromLocal8Bit("提示"), QString::fromLocal8Bit("经度为非数字")); return;
}
if (latOK == false)
{
QMessageBox::information(nullptr, QString::fromLocal8Bit("提示"), QString::fromLocal8Bit("纬度为非数字")); return;
}
m_cityList.push_back(city);
saveXML();
ui.lineEdit_name->clear();
ui.lineEdit_lon->clear();
ui.lineEdit_lat->clear();
load();
}
void OperateXml::del()
{
int num=ui.tableView->currentIndex().row();
//m_model->removeRow(num);
//获取选中行名称
QModelIndex index = m_model->index(num, 0);
QString name = m_model->data(index).toString();
std::vector

void OperateXml::load()
{

m_model = new QStandardItemModel();
m_model->setColumnCount(3);
m_model->setHeaderData(0, Qt::Horizontal, QString::fromLocal8Bit("名称"));
m_model->setHeaderData(1, Qt::Horizontal, QString::fromLocal8Bit("经度"));
m_model->setHeaderData(2, Qt::Horizontal, QString::fromLocal8Bit("纬度"));
if (!m_cityList.empty())
{
    for (int i = 0; i < m_cityList.size(); i++)
    {
        m_model->setItem(i, 0, new QStandardItem(m_cityList[i].name));
        m_model->setItem(i, 1, new QStandardItem(QString::number(m_cityList[i].lon)));
        m_model->setItem(i, 2, new QStandardItem(QString::number(m_cityList[i].lat)));
    }
}
ui.tableView->setModel(m_model);
ui.tableView->setSelectionBehavior(QAbstractItemView::SelectRows);

}
void OperateXml::readXML()
{
//打开或创建文件
QFile file("test.xml"); //相对路径、绝对路径、资源路径都行
if (!file.open(QFile::ReadOnly))
return;

QDomDocument doc;
if (!doc.setContent(&file))
{
    file.close();
    return;
}
file.close();

QDomElement root = doc.documentElement(); //返回根节点
QDomNode node = root.firstChild(); //获得第一个子节点
while (!node.isNull())  //如果节点不空
{
    if (node.isElement()) //如果节点是元素
    {
        cityInfo  city;
        QDomElement e = node.toElement(); //转换为元素，注意元素和节点是两个数据结构，其实差不多
        if (e.tagName() == "city")
        {
            city.name = e.attribute("name");
            city.lon = e.attribute("lon").toDouble();
            city.lat = e.attribute("lat").toDouble();
            m_cityList.push_back(city);
        }
    }
    node = node.nextSibling(); //下一个兄弟节点,nextSiblingElement()是下一个兄弟元素，都差不多
}

}
void OperateXml::saveXML()
{
//打开或创建文件
QFile file("test.xml"); //相对路径、绝对路径、资源路径都可以
if (!file.open(QFile::WriteOnly | QFile::Truncate)) //可以用QIODevice，Truncate表示清空原来的内容
return;

QDomDocument doc;
//写入xml头部
QDomProcessingInstruction instruction; //添加处理命令
instruction = doc.createProcessingInstruction("xml", "version="1.0" encoding="UTF-8"");
doc.appendChild(instruction);
//添加根节点
QDomElement root = doc.createElement("lib");
doc.appendChild(root);
int n = m_model->rowCount();
for (int i = 0; i < m_cityList.size(); i++)
{
    //添加一个子节点及其子元素
    QDomElement city = doc.createElement("city");
    /*QModelIndex indexName = m_model->index(i, 0);
    QModelIndex indexLon = m_model->index(i, 1);
    QModelIndex indexLat = m_model->index(i, 2);
    QString name = m_model->data(indexName).toString();
    QString lon = m_model->data(indexLon).toString();
    QString lat = m_model->data(indexLat).toString();*/

    city.setAttribute("name",m_cityList[i].name); //方式一：创建属性  其中键值对的值可以是各种类型
    city.setAttribute("lon", m_cityList[i].lon); //方式一：创建属性  其中键值对的值可以是各种类型
    city.setAttribute("lat", m_cityList[i].lat); //方式一：创建属性  其中键值对的值可以是各种类型
    root.appendChild(city);
}
//输出到文件
QTextStream out_stream(&file);
doc.save(out_stream, 4); //缩进4格
file.close();

}