32、Qt读写csv文件

一、写入

    QString fileName = QFileDialog::getSaveFileName(this, "写入", "/untitled.csv", tr("Files (*.csv)"));if(fileName.isEmpty()){QMessageBox::warning(this, "提示", "文件名不能为空", QMessageBox::Ok);return;}QFile file(fileName);bool ret = file.open(QIODevice::WriteOnly);if(!ret){QMessageBox::warning(this, "提示", QString("打开文件失败: %1").arg(file.errorString()), QMessageBox::Ok);return;}QString conTents;//表头conTents += "姓名";conTents += ",";conTents += "年龄";conTents += ",";conTents += "时间";conTents += "\n";conTents += "张三";conTents += ",";conTents += "23";conTents += ",";QString time = QDateTime::currentDateTime().toString("yyyy-MM-dd hh:mm:ss.zzz").replace(" ", "-"); //有空格会导致年月日被省略conTents += time;conTents += "\n";conTents += "李四";conTents += ",";conTents += "24";conTents += ",";time = QDateTime::currentDateTime().toString("yyyy-MM-dd hh:mm:ss.zzz").replace(" ", "-"); //有空格会导致年月日被省略conTents += time;conTents += "\n";conTents += "王五";conTents += ",";conTents += "25";conTents += ",";time = QDateTime::currentDateTime().toString("yyyy-MM-dd hh:mm:ss.zzz").replace(" ", "-"); //有空格会导致年月日被省略conTents += time;conTents += "\n";QByteArray baSave = QString(conTents).toLocal8Bit(); //格式转换file.write(baSave.data());file.close();

写入好的文件内容如下：

二、读取

void MainWindow::on_readPushButton_clicked()
{QString fileName = QFileDialog::getOpenFileName(this, "读取", "", tr("File (*.csv)"));QFile file(fileName);if(file.open(QIODevice::ReadOnly)) //只读方式打开文件{while(!file.atEnd()){QString strLine = GetCorrectUnicode(file.readLine()); //格式转换strLine.remove("\n"); //去掉结尾换行符号QStringList strLineList = strLine.split(",");if(strLineList.size() > 1){qDebug() << strLineList.at(0) << strLineList.at(1) << strLineList.at(2);}}file.close();}
}QString MainWindow::GetCorrectUnicode(const QByteArray &ba)
{// state用于保存转换状态，它的成员invalidChars，可用来判断是否转换成功// 如果转换成功，则值为0，如果值大于0，则说明转换失败QTextCodec::ConverterState state;// 先尝试使用utf-8的方式把QByteArray转换成QStringQString text = QTextCodec::codecForName("UTF-8")->toUnicode(ba.constData(), ba.size(), &state);// 如果转换时无效字符数量大于0，说明编码格式不对if (state.invalidChars > 0){// 再尝试使用GBK的方式进行转换，一般就能转换正确(当然也可能是其它格式，但比较少见了)text = QTextCodec::codecForName("GBK")->toUnicode(ba);}return text;
}

读取的内容如下：