#include #include #include #include #include // Still needed for parsing the content #include #include int main(int argc, char *argv[]) { QApplication app(argc, argv); auto fileContentReady = [](const QString &fileName, const QByteArray &fileContent) { if (fileName.isEmpty() || !QFile(fileName).exists()) { std::cerr << "Failed to open file" << std::endl; return; } QString contentStr(fileContent); QTextStream in(&contentStr); QString line = in.readLine(); bool ok; int number = line.toInt(&ok); if (!ok) { std::cerr << "Failed to read integer from file content" << std::endl; return; } std::cout << number * 2 << std::endl; }; QFileDialog::getOpenFileContent("All Files (*.*)", fileContentReady); }