static bool creatConnection()
{
//creat a database
QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE","connection1");
db.setDatabaseName("my1.db");
db = QSqlDatabase::database("connection1"); //建立数据库连接
if(!db.open()){
QMessageBox::critical(0,"Cannot open database1",
"Unable to establish a database connection.",QMessageBox::Cancel);
return false;
}
QSqlQuery query1(db);
query1.exec("create table shuju (Datetime QDateTime primary key,yanwu float,Temperature float,Humidity float)");
return true;
}
void SocketTCPServer::ReadDataFromSqlWriteToCSV(const QString &tableName,const QString &csvFileName)//将表导出为csv格式表格
{
QSqlTableModel *exportModel = new QSqlTableModel();
exportModel->setTable(tableName);
exportModel->select();
QStringList strList;//记录数据库中的一行报警数据
QString strString;
const QString FILE_PATH(csvFileName);
QFile csvFile(FILE_PATH);
if (csvFile.open(QIODevice::ReadWrite))
{
for (int i=0;i<exportModel->rowCount();i++)
{
for(int j=0;j<exportModel->columnCount();j++)
{
strList.insert(j,exportModel->data(exportModel->index(i,j)).toString());//把每一行的每一列数据读取到strList中
}
strString = strList.join(", ")+"\n";//给两个列数据之前加“,”号，一行数据末尾加回车
strList.clear();//记录一行数据后清空，再记下一行数据
csvFile.write(strString.toUtf8());//使用方法：转换为Utf8格式后在windows下的excel打开是乱码,可先用notepad++打开并转码为unicode，再次用excel打开即可。
qDebug()<<strString.toUtf8();
}
csvFile.close();
}
}
void SocketTCPServer::on_daochushuju_clicked()
{
ReadDataFromSqlWriteToCSV("shuju","shuju.csv");
}
