Qt将图片保存为XML文件或者变为QSting

2019-11-11 05:06:23

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来源：转载

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软件实现

只能打开用这个软件生成的xml文件，因为标签不一样有可能导致错误

mainwindow.h

#ifndef MAINWINDOW_H#define MAINWINDOW_H#include <QMainWindow>namespace Ui {class MainWindow;}class MainWindow : public QMainWindow{ Q_OBJECTpublic: explicit MainWindow(QWidget *parent = 0); ~MainWindow();PRivate slots: void on_loadImageBtn_clicked(); void on_saveBtn_clicked(); void on_loadXmlBtn_clicked();private: Ui::MainWindow *ui;};#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"#include "ui_mainwindow.h"#include <QFile>#include <QFileDialog>#include <QMessageBox>#include <QTextStream>#include <QPixmap>#include <QDebug>#include <QByteArray>#include <QBuffer>#include <QXmlStreamWriter>MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow){ ui->setupUi(this);}MainWindow::~MainWindow(){ delete ui;}void MainWindow::on_loadImageBtn_clicked(){ QString line; //file1文件保存的是上一次打开文件的地址 QFile file1("/savefile.txt"); if(file1.open(QIODevice::ReadOnly)) { QTextStream in(&file1); line = in.readLine(); } file1.close(); QString fileName = QFileDialog::getOpenFileName(this,"Open Image",line,tr("Image files(*.png *.jpg *.bmp)")); //上面的这一部分操作保证的是打开的是上一次的上传的文件 //将这次打开的文件的地址重新写入到保存文件地址的文件中,如果用户没有重新选择就不用保存 if(fileName.isEmpty())//用户没选中文件，接着进行下面的操作就会崩溃,因为s是一个空字符串 return; if(file1.open((QIODevice::WriteOnly))) { QTextStream in(&file1); in<<fileName; } file1.close(); QImage *image = new QImage(); if(!image->load(fileName)) { QMessageBox::information(this,tr("Open Image Failed"),tr("Open Image Failed")); delete image; return; } else { ui->label->setPixmap(QPixmap::fromImage(*image)); }}void MainWindow::on_saveBtn_clicked(){ const QPixmap *pixmap = ui->label->pixmap(); QImage image = pixmap->toImage(); QByteArray ba; QBuffer buffer(&ba); if(!buffer.open(QIODevice::WriteOnly)) { QMessageBox::information(this,tr("Save Xml"),tr("Save Xml Failed")); } //必须指明保存格式 image.save(&buffer,"PNG"); buffer.close(); QByteArray array = ba.toHex(); QString temp = array; QFile file("my.xml"); if(!file.open(QFile::WriteOnly | QFile::Text)) return; QXmlStreamWriter stream(&file); stream.setAutoFormatting(true); stream.writeStartDocument(); stream.writeStartElement("file"); stream.writeTextElement("image",temp); stream.writeEndElement(); stream.writeEndDocument(); file.close();}void MainWindow::on_loadXmlBtn_clicked(){ QString fileName = QFileDialog::getOpenFileName(this,"Open Xml","",tr("Image files(*.xml)")); QFile file(fileName); if(!file.open(QFile::ReadOnly | QFile::Text)) return; QXmlStreamReader reader(&file); // 如果没有读到文档结尾，而且没有出现错误 while (!reader.atEnd()) { // 读取下一个记号，它返回记号的类型 QXmlStreamReader::TokenType type = reader.readNext(); if (type == QXmlStreamReader::Characters && !reader.isWhitespace()) { QPixmap pixmap; pixmap.loadFromData(QByteArray::fromHex(reader.text().toLatin1())); ui->label->setPixmap(pixmap); } }}

这里写图片描述