Table of content

• About project
• Building
• Usage
• Classes

About project

This is a library for importing and exporting data. Created as a result of the division of Volbx project code and moving parts of it to an independent library. The library contains classes:

• ExportData (base class for exporting)
• ExportXlsx
• ExportDsv
• ImportSpreadsheet (base class for spreadsheet importing)
• ImportOds
• ImportXlsx

The library is based on Qt 6 and C++17. It uses the Zlib and QuaZip projects.

Building

Clone and use CMake directly or via Qt Creator. CMake should:

• configure everything automatically,
• compile library and create binaries.

TIP 1: remember to set properly CMAKE_PREFIX_PATH env variable. It should have a Qt installation path to let CMake use find_package command.

TIP 2: make sure you install the Core5Compat module, which is part of Qt 6 as Quazip needs it.

As a result of compilation, a dynamic lib should be created along with a headers' dir.

Check out my other project, Volbx to familiarize yourself with how to use it via CMake.

Used tools and libs

Tool	Windows	Lubuntu
OS version	10 22H2	22.04
GCC	11.2.0	11.3.0
CMake	3.25.0	3.25.0
Git	2.38.1	2.34.1
Qt	6.5.2	6.5.2
Qt Creator	10.0.2	10.0.2
Zlib	1.2.13	1.2.13
QuaZip	1.4	1.4

Usage

The easiest way is to check the examples' subproject, where you can find how to create and interact with each class included in this library.
Alternatively, tests in a subproject can be checked. Usage can also be found in my other project called Volbx where classes from this library are used for exporting and importing data.

Classes

Classes used for importing data

ImportSpreadsheet

Base class for spreadsheet-related import classes. The following pure virtual methods need to be implemented when creating a new derived class:

• getSheetNames()
• getColumnNames()
• getColumnTypes()
• getCount()
• getLimitedData()
• retrieveColumnNames()
• retrieveRowCountAndColumnTypes()

Emits signal progressPercentChanged during loading data.

Importing can be done from objects with the interface QIODevice: files on disk, files from resources, QBuffer and more.

ImportXlsx

Class used to import data from .xlsx files. Basic usage:

QFile xlsxFile("example.xlsx");
ImportXlsx importXlsx(xlsxFile);
auto [success, xlsxData] = importXlsx.getData("SheetName", {});

Check example and test subprojects for more advanced use cases.
Take note that .xlsx files store strings separately. ImportXlsx follows that convention and provides getSharedStrings() to retrieve those.

ImportOds

Class used to import data from .ods files. Basic usage:

QFile odsFile("example.ods");
ImportOds importOds(odsFile);
auto [success, odsData] = importOds.getData("SheetName", {});

Check example and test subprojects for more advanced use cases.

Classes used for exporting data

ExportData

Base class for export-related classes. The following pure virtual methods need to be implemented when creating a new derived class:

• writeContent()
• getEmptyContent()
• generateHeaderContent()
• generateRowContent()

Emits signal progressPercentChanged during loading data.

Data can be exported to objects with the interface QIODevice. It can be not only a QFile but also QBuffer. Example of exporting data into memory:

QByteArray exportedZipBuffer;
QBuffer exportedZip(&exportedZipBuffer);
exportedZip.open(QIODevice::WriteOnly);
QTableWidget tableWidget;
ExportXlsx exportXlsx;
exportXlsx.exportView(tableWidget, exportedZip);

ExportDsv

Class for exporting data to DSV (Delimiter Separated Values) files. The delimiter is set in the constructor and can be any character (comma, tab, semicolon, ...). CSV or TSV files can be created using this class.
Three additional methods can be used to customize the output:

• setDateFormat(Qt::DateFormat) - for setting the output date format to a given one,
• setDateFormat(QString) - for setting the output date format to one given as a string (for example, "dd/MM/yy"),
• setNumbersLocale(QLocale)- for setting the locale used for output numbers in case a different one from the default one is needed.

Basic usage:

QFile outFile("example.csv");
outFile.open(QIODevice::WriteOnly);
QTableWidget tableWidget;
ExportDsv exportDsv(',');
exportDsv.exportView(tableWidget, outFile);

ExportXlsx

Class for exporting data to .xlsx files.
Basic usage:

QFile outFile("example.xlsx");
outFile.open(QIODevice::WriteOnly);
QTableWidget tableWidget;
ExportXlsx exportXlsx;
exportXlsx.exportView(tableWidget, outFile);

XLSX files are created using the template file template.xlsx included in the project via the resource collection file resources.qrc.